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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * kernel/cpuset.c | |
3 | * | |
4 | * Processor and Memory placement constraints for sets of tasks. | |
5 | * | |
6 | * Copyright (C) 2003 BULL SA. | |
029190c5 | 7 | * Copyright (C) 2004-2007 Silicon Graphics, Inc. |
8793d854 | 8 | * Copyright (C) 2006 Google, Inc |
1da177e4 LT |
9 | * |
10 | * Portions derived from Patrick Mochel's sysfs code. | |
11 | * sysfs is Copyright (c) 2001-3 Patrick Mochel | |
1da177e4 | 12 | * |
825a46af | 13 | * 2003-10-10 Written by Simon Derr. |
1da177e4 | 14 | * 2003-10-22 Updates by Stephen Hemminger. |
825a46af | 15 | * 2004 May-July Rework by Paul Jackson. |
8793d854 | 16 | * 2006 Rework by Paul Menage to use generic cgroups |
cf417141 MK |
17 | * 2008 Rework of the scheduler domains and CPU hotplug handling |
18 | * by Max Krasnyansky | |
1da177e4 LT |
19 | * |
20 | * This file is subject to the terms and conditions of the GNU General Public | |
21 | * License. See the file COPYING in the main directory of the Linux | |
22 | * distribution for more details. | |
23 | */ | |
24 | ||
1da177e4 LT |
25 | #include <linux/cpu.h> |
26 | #include <linux/cpumask.h> | |
27 | #include <linux/cpuset.h> | |
28 | #include <linux/err.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/file.h> | |
31 | #include <linux/fs.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/interrupt.h> | |
34 | #include <linux/kernel.h> | |
35 | #include <linux/kmod.h> | |
36 | #include <linux/list.h> | |
68860ec1 | 37 | #include <linux/mempolicy.h> |
1da177e4 | 38 | #include <linux/mm.h> |
f481891f | 39 | #include <linux/memory.h> |
9984de1a | 40 | #include <linux/export.h> |
1da177e4 LT |
41 | #include <linux/mount.h> |
42 | #include <linux/namei.h> | |
43 | #include <linux/pagemap.h> | |
44 | #include <linux/proc_fs.h> | |
6b9c2603 | 45 | #include <linux/rcupdate.h> |
1da177e4 LT |
46 | #include <linux/sched.h> |
47 | #include <linux/seq_file.h> | |
22fb52dd | 48 | #include <linux/security.h> |
1da177e4 | 49 | #include <linux/slab.h> |
1da177e4 LT |
50 | #include <linux/spinlock.h> |
51 | #include <linux/stat.h> | |
52 | #include <linux/string.h> | |
53 | #include <linux/time.h> | |
54 | #include <linux/backing-dev.h> | |
55 | #include <linux/sort.h> | |
56 | ||
57 | #include <asm/uaccess.h> | |
60063497 | 58 | #include <linux/atomic.h> |
3d3f26a7 | 59 | #include <linux/mutex.h> |
956db3ca CW |
60 | #include <linux/workqueue.h> |
61 | #include <linux/cgroup.h> | |
e44193d3 | 62 | #include <linux/wait.h> |
1da177e4 | 63 | |
202f72d5 PJ |
64 | /* |
65 | * Tracks how many cpusets are currently defined in system. | |
66 | * When there is only one cpuset (the root cpuset) we can | |
67 | * short circuit some hooks. | |
68 | */ | |
7edc5962 | 69 | int number_of_cpusets __read_mostly; |
202f72d5 | 70 | |
2df167a3 | 71 | /* Forward declare cgroup structures */ |
8793d854 PM |
72 | struct cgroup_subsys cpuset_subsys; |
73 | struct cpuset; | |
74 | ||
3e0d98b9 PJ |
75 | /* See "Frequency meter" comments, below. */ |
76 | ||
77 | struct fmeter { | |
78 | int cnt; /* unprocessed events count */ | |
79 | int val; /* most recent output value */ | |
80 | time_t time; /* clock (secs) when val computed */ | |
81 | spinlock_t lock; /* guards read or write of above */ | |
82 | }; | |
83 | ||
1da177e4 | 84 | struct cpuset { |
8793d854 PM |
85 | struct cgroup_subsys_state css; |
86 | ||
1da177e4 | 87 | unsigned long flags; /* "unsigned long" so bitops work */ |
300ed6cb | 88 | cpumask_var_t cpus_allowed; /* CPUs allowed to tasks in cpuset */ |
1da177e4 LT |
89 | nodemask_t mems_allowed; /* Memory Nodes allowed to tasks */ |
90 | ||
33ad801d LZ |
91 | /* |
92 | * This is old Memory Nodes tasks took on. | |
93 | * | |
94 | * - top_cpuset.old_mems_allowed is initialized to mems_allowed. | |
95 | * - A new cpuset's old_mems_allowed is initialized when some | |
96 | * task is moved into it. | |
97 | * - old_mems_allowed is used in cpuset_migrate_mm() when we change | |
98 | * cpuset.mems_allowed and have tasks' nodemask updated, and | |
99 | * then old_mems_allowed is updated to mems_allowed. | |
100 | */ | |
101 | nodemask_t old_mems_allowed; | |
102 | ||
3e0d98b9 | 103 | struct fmeter fmeter; /* memory_pressure filter */ |
029190c5 | 104 | |
452477fa TH |
105 | /* |
106 | * Tasks are being attached to this cpuset. Used to prevent | |
107 | * zeroing cpus/mems_allowed between ->can_attach() and ->attach(). | |
108 | */ | |
109 | int attach_in_progress; | |
110 | ||
029190c5 PJ |
111 | /* partition number for rebuild_sched_domains() */ |
112 | int pn; | |
956db3ca | 113 | |
1d3504fc HS |
114 | /* for custom sched domain */ |
115 | int relax_domain_level; | |
1da177e4 LT |
116 | }; |
117 | ||
8793d854 | 118 | /* Retrieve the cpuset for a cgroup */ |
c9e5fe66 | 119 | static inline struct cpuset *cgroup_cs(struct cgroup *cgrp) |
8793d854 | 120 | { |
c9e5fe66 | 121 | return container_of(cgroup_subsys_state(cgrp, cpuset_subsys_id), |
8793d854 PM |
122 | struct cpuset, css); |
123 | } | |
124 | ||
125 | /* Retrieve the cpuset for a task */ | |
126 | static inline struct cpuset *task_cs(struct task_struct *task) | |
127 | { | |
128 | return container_of(task_subsys_state(task, cpuset_subsys_id), | |
129 | struct cpuset, css); | |
130 | } | |
8793d854 | 131 | |
c431069f TH |
132 | static inline struct cpuset *parent_cs(const struct cpuset *cs) |
133 | { | |
134 | struct cgroup *pcgrp = cs->css.cgroup->parent; | |
135 | ||
136 | if (pcgrp) | |
137 | return cgroup_cs(pcgrp); | |
138 | return NULL; | |
139 | } | |
140 | ||
b246272e DR |
141 | #ifdef CONFIG_NUMA |
142 | static inline bool task_has_mempolicy(struct task_struct *task) | |
143 | { | |
144 | return task->mempolicy; | |
145 | } | |
146 | #else | |
147 | static inline bool task_has_mempolicy(struct task_struct *task) | |
148 | { | |
149 | return false; | |
150 | } | |
151 | #endif | |
152 | ||
153 | ||
1da177e4 LT |
154 | /* bits in struct cpuset flags field */ |
155 | typedef enum { | |
efeb77b2 | 156 | CS_ONLINE, |
1da177e4 LT |
157 | CS_CPU_EXCLUSIVE, |
158 | CS_MEM_EXCLUSIVE, | |
78608366 | 159 | CS_MEM_HARDWALL, |
45b07ef3 | 160 | CS_MEMORY_MIGRATE, |
029190c5 | 161 | CS_SCHED_LOAD_BALANCE, |
825a46af PJ |
162 | CS_SPREAD_PAGE, |
163 | CS_SPREAD_SLAB, | |
1da177e4 LT |
164 | } cpuset_flagbits_t; |
165 | ||
166 | /* convenient tests for these bits */ | |
efeb77b2 TH |
167 | static inline bool is_cpuset_online(const struct cpuset *cs) |
168 | { | |
169 | return test_bit(CS_ONLINE, &cs->flags); | |
170 | } | |
171 | ||
1da177e4 LT |
172 | static inline int is_cpu_exclusive(const struct cpuset *cs) |
173 | { | |
7b5b9ef0 | 174 | return test_bit(CS_CPU_EXCLUSIVE, &cs->flags); |
1da177e4 LT |
175 | } |
176 | ||
177 | static inline int is_mem_exclusive(const struct cpuset *cs) | |
178 | { | |
7b5b9ef0 | 179 | return test_bit(CS_MEM_EXCLUSIVE, &cs->flags); |
1da177e4 LT |
180 | } |
181 | ||
78608366 PM |
182 | static inline int is_mem_hardwall(const struct cpuset *cs) |
183 | { | |
184 | return test_bit(CS_MEM_HARDWALL, &cs->flags); | |
185 | } | |
186 | ||
029190c5 PJ |
187 | static inline int is_sched_load_balance(const struct cpuset *cs) |
188 | { | |
189 | return test_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); | |
190 | } | |
191 | ||
45b07ef3 PJ |
192 | static inline int is_memory_migrate(const struct cpuset *cs) |
193 | { | |
7b5b9ef0 | 194 | return test_bit(CS_MEMORY_MIGRATE, &cs->flags); |
45b07ef3 PJ |
195 | } |
196 | ||
825a46af PJ |
197 | static inline int is_spread_page(const struct cpuset *cs) |
198 | { | |
199 | return test_bit(CS_SPREAD_PAGE, &cs->flags); | |
200 | } | |
201 | ||
202 | static inline int is_spread_slab(const struct cpuset *cs) | |
203 | { | |
204 | return test_bit(CS_SPREAD_SLAB, &cs->flags); | |
205 | } | |
206 | ||
1da177e4 | 207 | static struct cpuset top_cpuset = { |
efeb77b2 TH |
208 | .flags = ((1 << CS_ONLINE) | (1 << CS_CPU_EXCLUSIVE) | |
209 | (1 << CS_MEM_EXCLUSIVE)), | |
1da177e4 LT |
210 | }; |
211 | ||
ae8086ce TH |
212 | /** |
213 | * cpuset_for_each_child - traverse online children of a cpuset | |
214 | * @child_cs: loop cursor pointing to the current child | |
215 | * @pos_cgrp: used for iteration | |
216 | * @parent_cs: target cpuset to walk children of | |
217 | * | |
218 | * Walk @child_cs through the online children of @parent_cs. Must be used | |
219 | * with RCU read locked. | |
220 | */ | |
221 | #define cpuset_for_each_child(child_cs, pos_cgrp, parent_cs) \ | |
222 | cgroup_for_each_child((pos_cgrp), (parent_cs)->css.cgroup) \ | |
223 | if (is_cpuset_online(((child_cs) = cgroup_cs((pos_cgrp))))) | |
224 | ||
fc560a26 TH |
225 | /** |
226 | * cpuset_for_each_descendant_pre - pre-order walk of a cpuset's descendants | |
227 | * @des_cs: loop cursor pointing to the current descendant | |
228 | * @pos_cgrp: used for iteration | |
229 | * @root_cs: target cpuset to walk ancestor of | |
230 | * | |
231 | * Walk @des_cs through the online descendants of @root_cs. Must be used | |
232 | * with RCU read locked. The caller may modify @pos_cgrp by calling | |
233 | * cgroup_rightmost_descendant() to skip subtree. | |
234 | */ | |
235 | #define cpuset_for_each_descendant_pre(des_cs, pos_cgrp, root_cs) \ | |
236 | cgroup_for_each_descendant_pre((pos_cgrp), (root_cs)->css.cgroup) \ | |
237 | if (is_cpuset_online(((des_cs) = cgroup_cs((pos_cgrp))))) | |
238 | ||
1da177e4 | 239 | /* |
5d21cc2d TH |
240 | * There are two global mutexes guarding cpuset structures - cpuset_mutex |
241 | * and callback_mutex. The latter may nest inside the former. We also | |
242 | * require taking task_lock() when dereferencing a task's cpuset pointer. | |
243 | * See "The task_lock() exception", at the end of this comment. | |
244 | * | |
245 | * A task must hold both mutexes to modify cpusets. If a task holds | |
246 | * cpuset_mutex, then it blocks others wanting that mutex, ensuring that it | |
247 | * is the only task able to also acquire callback_mutex and be able to | |
248 | * modify cpusets. It can perform various checks on the cpuset structure | |
249 | * first, knowing nothing will change. It can also allocate memory while | |
250 | * just holding cpuset_mutex. While it is performing these checks, various | |
251 | * callback routines can briefly acquire callback_mutex to query cpusets. | |
252 | * Once it is ready to make the changes, it takes callback_mutex, blocking | |
253 | * everyone else. | |
053199ed PJ |
254 | * |
255 | * Calls to the kernel memory allocator can not be made while holding | |
3d3f26a7 | 256 | * callback_mutex, as that would risk double tripping on callback_mutex |
053199ed PJ |
257 | * from one of the callbacks into the cpuset code from within |
258 | * __alloc_pages(). | |
259 | * | |
3d3f26a7 | 260 | * If a task is only holding callback_mutex, then it has read-only |
053199ed PJ |
261 | * access to cpusets. |
262 | * | |
58568d2a MX |
263 | * Now, the task_struct fields mems_allowed and mempolicy may be changed |
264 | * by other task, we use alloc_lock in the task_struct fields to protect | |
265 | * them. | |
053199ed | 266 | * |
3d3f26a7 | 267 | * The cpuset_common_file_read() handlers only hold callback_mutex across |
053199ed PJ |
268 | * small pieces of code, such as when reading out possibly multi-word |
269 | * cpumasks and nodemasks. | |
270 | * | |
2df167a3 PM |
271 | * Accessing a task's cpuset should be done in accordance with the |
272 | * guidelines for accessing subsystem state in kernel/cgroup.c | |
1da177e4 LT |
273 | */ |
274 | ||
5d21cc2d | 275 | static DEFINE_MUTEX(cpuset_mutex); |
3d3f26a7 | 276 | static DEFINE_MUTEX(callback_mutex); |
4247bdc6 | 277 | |
3a5a6d0c TH |
278 | /* |
279 | * CPU / memory hotplug is handled asynchronously. | |
280 | */ | |
281 | static void cpuset_hotplug_workfn(struct work_struct *work); | |
3a5a6d0c TH |
282 | static DECLARE_WORK(cpuset_hotplug_work, cpuset_hotplug_workfn); |
283 | ||
e44193d3 LZ |
284 | static DECLARE_WAIT_QUEUE_HEAD(cpuset_attach_wq); |
285 | ||
cf417141 MK |
286 | /* |
287 | * This is ugly, but preserves the userspace API for existing cpuset | |
8793d854 | 288 | * users. If someone tries to mount the "cpuset" filesystem, we |
cf417141 MK |
289 | * silently switch it to mount "cgroup" instead |
290 | */ | |
f7e83571 AV |
291 | static struct dentry *cpuset_mount(struct file_system_type *fs_type, |
292 | int flags, const char *unused_dev_name, void *data) | |
1da177e4 | 293 | { |
8793d854 | 294 | struct file_system_type *cgroup_fs = get_fs_type("cgroup"); |
f7e83571 | 295 | struct dentry *ret = ERR_PTR(-ENODEV); |
8793d854 PM |
296 | if (cgroup_fs) { |
297 | char mountopts[] = | |
298 | "cpuset,noprefix," | |
299 | "release_agent=/sbin/cpuset_release_agent"; | |
f7e83571 AV |
300 | ret = cgroup_fs->mount(cgroup_fs, flags, |
301 | unused_dev_name, mountopts); | |
8793d854 PM |
302 | put_filesystem(cgroup_fs); |
303 | } | |
304 | return ret; | |
1da177e4 LT |
305 | } |
306 | ||
307 | static struct file_system_type cpuset_fs_type = { | |
308 | .name = "cpuset", | |
f7e83571 | 309 | .mount = cpuset_mount, |
1da177e4 LT |
310 | }; |
311 | ||
1da177e4 | 312 | /* |
300ed6cb | 313 | * Return in pmask the portion of a cpusets's cpus_allowed that |
1da177e4 | 314 | * are online. If none are online, walk up the cpuset hierarchy |
40df2deb LZ |
315 | * until we find one that does have some online cpus. The top |
316 | * cpuset always has some cpus online. | |
1da177e4 LT |
317 | * |
318 | * One way or another, we guarantee to return some non-empty subset | |
5f054e31 | 319 | * of cpu_online_mask. |
1da177e4 | 320 | * |
3d3f26a7 | 321 | * Call with callback_mutex held. |
1da177e4 | 322 | */ |
6af866af LZ |
323 | static void guarantee_online_cpus(const struct cpuset *cs, |
324 | struct cpumask *pmask) | |
1da177e4 | 325 | { |
40df2deb | 326 | while (!cpumask_intersects(cs->cpus_allowed, cpu_online_mask)) |
c431069f | 327 | cs = parent_cs(cs); |
40df2deb | 328 | cpumask_and(pmask, cs->cpus_allowed, cpu_online_mask); |
1da177e4 LT |
329 | } |
330 | ||
331 | /* | |
332 | * Return in *pmask the portion of a cpusets's mems_allowed that | |
0e1e7c7a CL |
333 | * are online, with memory. If none are online with memory, walk |
334 | * up the cpuset hierarchy until we find one that does have some | |
40df2deb | 335 | * online mems. The top cpuset always has some mems online. |
1da177e4 LT |
336 | * |
337 | * One way or another, we guarantee to return some non-empty subset | |
38d7bee9 | 338 | * of node_states[N_MEMORY]. |
1da177e4 | 339 | * |
3d3f26a7 | 340 | * Call with callback_mutex held. |
1da177e4 | 341 | */ |
1da177e4 LT |
342 | static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask) |
343 | { | |
40df2deb | 344 | while (!nodes_intersects(cs->mems_allowed, node_states[N_MEMORY])) |
c431069f | 345 | cs = parent_cs(cs); |
40df2deb | 346 | nodes_and(*pmask, cs->mems_allowed, node_states[N_MEMORY]); |
1da177e4 LT |
347 | } |
348 | ||
f3b39d47 MX |
349 | /* |
350 | * update task's spread flag if cpuset's page/slab spread flag is set | |
351 | * | |
5d21cc2d | 352 | * Called with callback_mutex/cpuset_mutex held |
f3b39d47 MX |
353 | */ |
354 | static void cpuset_update_task_spread_flag(struct cpuset *cs, | |
355 | struct task_struct *tsk) | |
356 | { | |
357 | if (is_spread_page(cs)) | |
358 | tsk->flags |= PF_SPREAD_PAGE; | |
359 | else | |
360 | tsk->flags &= ~PF_SPREAD_PAGE; | |
361 | if (is_spread_slab(cs)) | |
362 | tsk->flags |= PF_SPREAD_SLAB; | |
363 | else | |
364 | tsk->flags &= ~PF_SPREAD_SLAB; | |
365 | } | |
366 | ||
1da177e4 LT |
367 | /* |
368 | * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q? | |
369 | * | |
370 | * One cpuset is a subset of another if all its allowed CPUs and | |
371 | * Memory Nodes are a subset of the other, and its exclusive flags | |
5d21cc2d | 372 | * are only set if the other's are set. Call holding cpuset_mutex. |
1da177e4 LT |
373 | */ |
374 | ||
375 | static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q) | |
376 | { | |
300ed6cb | 377 | return cpumask_subset(p->cpus_allowed, q->cpus_allowed) && |
1da177e4 LT |
378 | nodes_subset(p->mems_allowed, q->mems_allowed) && |
379 | is_cpu_exclusive(p) <= is_cpu_exclusive(q) && | |
380 | is_mem_exclusive(p) <= is_mem_exclusive(q); | |
381 | } | |
382 | ||
645fcc9d LZ |
383 | /** |
384 | * alloc_trial_cpuset - allocate a trial cpuset | |
385 | * @cs: the cpuset that the trial cpuset duplicates | |
386 | */ | |
387 | static struct cpuset *alloc_trial_cpuset(const struct cpuset *cs) | |
388 | { | |
300ed6cb LZ |
389 | struct cpuset *trial; |
390 | ||
391 | trial = kmemdup(cs, sizeof(*cs), GFP_KERNEL); | |
392 | if (!trial) | |
393 | return NULL; | |
394 | ||
395 | if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL)) { | |
396 | kfree(trial); | |
397 | return NULL; | |
398 | } | |
399 | cpumask_copy(trial->cpus_allowed, cs->cpus_allowed); | |
400 | ||
401 | return trial; | |
645fcc9d LZ |
402 | } |
403 | ||
404 | /** | |
405 | * free_trial_cpuset - free the trial cpuset | |
406 | * @trial: the trial cpuset to be freed | |
407 | */ | |
408 | static void free_trial_cpuset(struct cpuset *trial) | |
409 | { | |
300ed6cb | 410 | free_cpumask_var(trial->cpus_allowed); |
645fcc9d LZ |
411 | kfree(trial); |
412 | } | |
413 | ||
1da177e4 LT |
414 | /* |
415 | * validate_change() - Used to validate that any proposed cpuset change | |
416 | * follows the structural rules for cpusets. | |
417 | * | |
418 | * If we replaced the flag and mask values of the current cpuset | |
419 | * (cur) with those values in the trial cpuset (trial), would | |
420 | * our various subset and exclusive rules still be valid? Presumes | |
5d21cc2d | 421 | * cpuset_mutex held. |
1da177e4 LT |
422 | * |
423 | * 'cur' is the address of an actual, in-use cpuset. Operations | |
424 | * such as list traversal that depend on the actual address of the | |
425 | * cpuset in the list must use cur below, not trial. | |
426 | * | |
427 | * 'trial' is the address of bulk structure copy of cur, with | |
428 | * perhaps one or more of the fields cpus_allowed, mems_allowed, | |
429 | * or flags changed to new, trial values. | |
430 | * | |
431 | * Return 0 if valid, -errno if not. | |
432 | */ | |
433 | ||
434 | static int validate_change(const struct cpuset *cur, const struct cpuset *trial) | |
435 | { | |
c9e5fe66 | 436 | struct cgroup *cgrp; |
1da177e4 | 437 | struct cpuset *c, *par; |
ae8086ce TH |
438 | int ret; |
439 | ||
440 | rcu_read_lock(); | |
1da177e4 LT |
441 | |
442 | /* Each of our child cpusets must be a subset of us */ | |
ae8086ce | 443 | ret = -EBUSY; |
c9e5fe66 | 444 | cpuset_for_each_child(c, cgrp, cur) |
ae8086ce TH |
445 | if (!is_cpuset_subset(c, trial)) |
446 | goto out; | |
1da177e4 LT |
447 | |
448 | /* Remaining checks don't apply to root cpuset */ | |
ae8086ce | 449 | ret = 0; |
69604067 | 450 | if (cur == &top_cpuset) |
ae8086ce | 451 | goto out; |
1da177e4 | 452 | |
c431069f | 453 | par = parent_cs(cur); |
69604067 | 454 | |
1da177e4 | 455 | /* We must be a subset of our parent cpuset */ |
ae8086ce | 456 | ret = -EACCES; |
1da177e4 | 457 | if (!is_cpuset_subset(trial, par)) |
ae8086ce | 458 | goto out; |
1da177e4 | 459 | |
2df167a3 PM |
460 | /* |
461 | * If either I or some sibling (!= me) is exclusive, we can't | |
462 | * overlap | |
463 | */ | |
ae8086ce | 464 | ret = -EINVAL; |
c9e5fe66 | 465 | cpuset_for_each_child(c, cgrp, par) { |
1da177e4 LT |
466 | if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) && |
467 | c != cur && | |
300ed6cb | 468 | cpumask_intersects(trial->cpus_allowed, c->cpus_allowed)) |
ae8086ce | 469 | goto out; |
1da177e4 LT |
470 | if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && |
471 | c != cur && | |
472 | nodes_intersects(trial->mems_allowed, c->mems_allowed)) | |
ae8086ce | 473 | goto out; |
1da177e4 LT |
474 | } |
475 | ||
452477fa TH |
476 | /* |
477 | * Cpusets with tasks - existing or newly being attached - can't | |
478 | * have empty cpus_allowed or mems_allowed. | |
479 | */ | |
ae8086ce | 480 | ret = -ENOSPC; |
452477fa | 481 | if ((cgroup_task_count(cur->css.cgroup) || cur->attach_in_progress) && |
88fa523b | 482 | (cpumask_empty(trial->cpus_allowed) && |
ae8086ce TH |
483 | nodes_empty(trial->mems_allowed))) |
484 | goto out; | |
020958b6 | 485 | |
ae8086ce TH |
486 | ret = 0; |
487 | out: | |
488 | rcu_read_unlock(); | |
489 | return ret; | |
1da177e4 LT |
490 | } |
491 | ||
db7f47cf | 492 | #ifdef CONFIG_SMP |
029190c5 | 493 | /* |
cf417141 | 494 | * Helper routine for generate_sched_domains(). |
029190c5 PJ |
495 | * Do cpusets a, b have overlapping cpus_allowed masks? |
496 | */ | |
029190c5 PJ |
497 | static int cpusets_overlap(struct cpuset *a, struct cpuset *b) |
498 | { | |
300ed6cb | 499 | return cpumask_intersects(a->cpus_allowed, b->cpus_allowed); |
029190c5 PJ |
500 | } |
501 | ||
1d3504fc HS |
502 | static void |
503 | update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c) | |
504 | { | |
1d3504fc HS |
505 | if (dattr->relax_domain_level < c->relax_domain_level) |
506 | dattr->relax_domain_level = c->relax_domain_level; | |
507 | return; | |
508 | } | |
509 | ||
fc560a26 TH |
510 | static void update_domain_attr_tree(struct sched_domain_attr *dattr, |
511 | struct cpuset *root_cs) | |
f5393693 | 512 | { |
fc560a26 TH |
513 | struct cpuset *cp; |
514 | struct cgroup *pos_cgrp; | |
f5393693 | 515 | |
fc560a26 TH |
516 | rcu_read_lock(); |
517 | cpuset_for_each_descendant_pre(cp, pos_cgrp, root_cs) { | |
518 | /* skip the whole subtree if @cp doesn't have any CPU */ | |
519 | if (cpumask_empty(cp->cpus_allowed)) { | |
520 | pos_cgrp = cgroup_rightmost_descendant(pos_cgrp); | |
f5393693 | 521 | continue; |
fc560a26 | 522 | } |
f5393693 LJ |
523 | |
524 | if (is_sched_load_balance(cp)) | |
525 | update_domain_attr(dattr, cp); | |
f5393693 | 526 | } |
fc560a26 | 527 | rcu_read_unlock(); |
f5393693 LJ |
528 | } |
529 | ||
029190c5 | 530 | /* |
cf417141 MK |
531 | * generate_sched_domains() |
532 | * | |
533 | * This function builds a partial partition of the systems CPUs | |
534 | * A 'partial partition' is a set of non-overlapping subsets whose | |
535 | * union is a subset of that set. | |
0a0fca9d | 536 | * The output of this function needs to be passed to kernel/sched/core.c |
cf417141 MK |
537 | * partition_sched_domains() routine, which will rebuild the scheduler's |
538 | * load balancing domains (sched domains) as specified by that partial | |
539 | * partition. | |
029190c5 | 540 | * |
45ce80fb | 541 | * See "What is sched_load_balance" in Documentation/cgroups/cpusets.txt |
029190c5 PJ |
542 | * for a background explanation of this. |
543 | * | |
544 | * Does not return errors, on the theory that the callers of this | |
545 | * routine would rather not worry about failures to rebuild sched | |
546 | * domains when operating in the severe memory shortage situations | |
547 | * that could cause allocation failures below. | |
548 | * | |
5d21cc2d | 549 | * Must be called with cpuset_mutex held. |
029190c5 PJ |
550 | * |
551 | * The three key local variables below are: | |
aeed6824 | 552 | * q - a linked-list queue of cpuset pointers, used to implement a |
029190c5 PJ |
553 | * top-down scan of all cpusets. This scan loads a pointer |
554 | * to each cpuset marked is_sched_load_balance into the | |
555 | * array 'csa'. For our purposes, rebuilding the schedulers | |
556 | * sched domains, we can ignore !is_sched_load_balance cpusets. | |
557 | * csa - (for CpuSet Array) Array of pointers to all the cpusets | |
558 | * that need to be load balanced, for convenient iterative | |
559 | * access by the subsequent code that finds the best partition, | |
560 | * i.e the set of domains (subsets) of CPUs such that the | |
561 | * cpus_allowed of every cpuset marked is_sched_load_balance | |
562 | * is a subset of one of these domains, while there are as | |
563 | * many such domains as possible, each as small as possible. | |
564 | * doms - Conversion of 'csa' to an array of cpumasks, for passing to | |
0a0fca9d | 565 | * the kernel/sched/core.c routine partition_sched_domains() in a |
029190c5 PJ |
566 | * convenient format, that can be easily compared to the prior |
567 | * value to determine what partition elements (sched domains) | |
568 | * were changed (added or removed.) | |
569 | * | |
570 | * Finding the best partition (set of domains): | |
571 | * The triple nested loops below over i, j, k scan over the | |
572 | * load balanced cpusets (using the array of cpuset pointers in | |
573 | * csa[]) looking for pairs of cpusets that have overlapping | |
574 | * cpus_allowed, but which don't have the same 'pn' partition | |
575 | * number and gives them in the same partition number. It keeps | |
576 | * looping on the 'restart' label until it can no longer find | |
577 | * any such pairs. | |
578 | * | |
579 | * The union of the cpus_allowed masks from the set of | |
580 | * all cpusets having the same 'pn' value then form the one | |
581 | * element of the partition (one sched domain) to be passed to | |
582 | * partition_sched_domains(). | |
583 | */ | |
acc3f5d7 | 584 | static int generate_sched_domains(cpumask_var_t **domains, |
cf417141 | 585 | struct sched_domain_attr **attributes) |
029190c5 | 586 | { |
029190c5 PJ |
587 | struct cpuset *cp; /* scans q */ |
588 | struct cpuset **csa; /* array of all cpuset ptrs */ | |
589 | int csn; /* how many cpuset ptrs in csa so far */ | |
590 | int i, j, k; /* indices for partition finding loops */ | |
acc3f5d7 | 591 | cpumask_var_t *doms; /* resulting partition; i.e. sched domains */ |
1d3504fc | 592 | struct sched_domain_attr *dattr; /* attributes for custom domains */ |
1583715d | 593 | int ndoms = 0; /* number of sched domains in result */ |
6af866af | 594 | int nslot; /* next empty doms[] struct cpumask slot */ |
fc560a26 | 595 | struct cgroup *pos_cgrp; |
029190c5 | 596 | |
029190c5 | 597 | doms = NULL; |
1d3504fc | 598 | dattr = NULL; |
cf417141 | 599 | csa = NULL; |
029190c5 PJ |
600 | |
601 | /* Special case for the 99% of systems with one, full, sched domain */ | |
602 | if (is_sched_load_balance(&top_cpuset)) { | |
acc3f5d7 RR |
603 | ndoms = 1; |
604 | doms = alloc_sched_domains(ndoms); | |
029190c5 | 605 | if (!doms) |
cf417141 MK |
606 | goto done; |
607 | ||
1d3504fc HS |
608 | dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL); |
609 | if (dattr) { | |
610 | *dattr = SD_ATTR_INIT; | |
93a65575 | 611 | update_domain_attr_tree(dattr, &top_cpuset); |
1d3504fc | 612 | } |
acc3f5d7 | 613 | cpumask_copy(doms[0], top_cpuset.cpus_allowed); |
cf417141 | 614 | |
cf417141 | 615 | goto done; |
029190c5 PJ |
616 | } |
617 | ||
029190c5 PJ |
618 | csa = kmalloc(number_of_cpusets * sizeof(cp), GFP_KERNEL); |
619 | if (!csa) | |
620 | goto done; | |
621 | csn = 0; | |
622 | ||
fc560a26 TH |
623 | rcu_read_lock(); |
624 | cpuset_for_each_descendant_pre(cp, pos_cgrp, &top_cpuset) { | |
f5393693 | 625 | /* |
fc560a26 TH |
626 | * Continue traversing beyond @cp iff @cp has some CPUs and |
627 | * isn't load balancing. The former is obvious. The | |
628 | * latter: All child cpusets contain a subset of the | |
629 | * parent's cpus, so just skip them, and then we call | |
630 | * update_domain_attr_tree() to calc relax_domain_level of | |
631 | * the corresponding sched domain. | |
f5393693 | 632 | */ |
fc560a26 TH |
633 | if (!cpumask_empty(cp->cpus_allowed) && |
634 | !is_sched_load_balance(cp)) | |
f5393693 | 635 | continue; |
489a5393 | 636 | |
fc560a26 TH |
637 | if (is_sched_load_balance(cp)) |
638 | csa[csn++] = cp; | |
639 | ||
640 | /* skip @cp's subtree */ | |
641 | pos_cgrp = cgroup_rightmost_descendant(pos_cgrp); | |
642 | } | |
643 | rcu_read_unlock(); | |
029190c5 PJ |
644 | |
645 | for (i = 0; i < csn; i++) | |
646 | csa[i]->pn = i; | |
647 | ndoms = csn; | |
648 | ||
649 | restart: | |
650 | /* Find the best partition (set of sched domains) */ | |
651 | for (i = 0; i < csn; i++) { | |
652 | struct cpuset *a = csa[i]; | |
653 | int apn = a->pn; | |
654 | ||
655 | for (j = 0; j < csn; j++) { | |
656 | struct cpuset *b = csa[j]; | |
657 | int bpn = b->pn; | |
658 | ||
659 | if (apn != bpn && cpusets_overlap(a, b)) { | |
660 | for (k = 0; k < csn; k++) { | |
661 | struct cpuset *c = csa[k]; | |
662 | ||
663 | if (c->pn == bpn) | |
664 | c->pn = apn; | |
665 | } | |
666 | ndoms--; /* one less element */ | |
667 | goto restart; | |
668 | } | |
669 | } | |
670 | } | |
671 | ||
cf417141 MK |
672 | /* |
673 | * Now we know how many domains to create. | |
674 | * Convert <csn, csa> to <ndoms, doms> and populate cpu masks. | |
675 | */ | |
acc3f5d7 | 676 | doms = alloc_sched_domains(ndoms); |
700018e0 | 677 | if (!doms) |
cf417141 | 678 | goto done; |
cf417141 MK |
679 | |
680 | /* | |
681 | * The rest of the code, including the scheduler, can deal with | |
682 | * dattr==NULL case. No need to abort if alloc fails. | |
683 | */ | |
1d3504fc | 684 | dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL); |
029190c5 PJ |
685 | |
686 | for (nslot = 0, i = 0; i < csn; i++) { | |
687 | struct cpuset *a = csa[i]; | |
6af866af | 688 | struct cpumask *dp; |
029190c5 PJ |
689 | int apn = a->pn; |
690 | ||
cf417141 MK |
691 | if (apn < 0) { |
692 | /* Skip completed partitions */ | |
693 | continue; | |
694 | } | |
695 | ||
acc3f5d7 | 696 | dp = doms[nslot]; |
cf417141 MK |
697 | |
698 | if (nslot == ndoms) { | |
699 | static int warnings = 10; | |
700 | if (warnings) { | |
701 | printk(KERN_WARNING | |
702 | "rebuild_sched_domains confused:" | |
703 | " nslot %d, ndoms %d, csn %d, i %d," | |
704 | " apn %d\n", | |
705 | nslot, ndoms, csn, i, apn); | |
706 | warnings--; | |
029190c5 | 707 | } |
cf417141 MK |
708 | continue; |
709 | } | |
029190c5 | 710 | |
6af866af | 711 | cpumask_clear(dp); |
cf417141 MK |
712 | if (dattr) |
713 | *(dattr + nslot) = SD_ATTR_INIT; | |
714 | for (j = i; j < csn; j++) { | |
715 | struct cpuset *b = csa[j]; | |
716 | ||
717 | if (apn == b->pn) { | |
300ed6cb | 718 | cpumask_or(dp, dp, b->cpus_allowed); |
cf417141 MK |
719 | if (dattr) |
720 | update_domain_attr_tree(dattr + nslot, b); | |
721 | ||
722 | /* Done with this partition */ | |
723 | b->pn = -1; | |
029190c5 | 724 | } |
029190c5 | 725 | } |
cf417141 | 726 | nslot++; |
029190c5 PJ |
727 | } |
728 | BUG_ON(nslot != ndoms); | |
729 | ||
cf417141 MK |
730 | done: |
731 | kfree(csa); | |
732 | ||
700018e0 LZ |
733 | /* |
734 | * Fallback to the default domain if kmalloc() failed. | |
735 | * See comments in partition_sched_domains(). | |
736 | */ | |
737 | if (doms == NULL) | |
738 | ndoms = 1; | |
739 | ||
cf417141 MK |
740 | *domains = doms; |
741 | *attributes = dattr; | |
742 | return ndoms; | |
743 | } | |
744 | ||
745 | /* | |
746 | * Rebuild scheduler domains. | |
747 | * | |
699140ba TH |
748 | * If the flag 'sched_load_balance' of any cpuset with non-empty |
749 | * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset | |
750 | * which has that flag enabled, or if any cpuset with a non-empty | |
751 | * 'cpus' is removed, then call this routine to rebuild the | |
752 | * scheduler's dynamic sched domains. | |
cf417141 | 753 | * |
5d21cc2d | 754 | * Call with cpuset_mutex held. Takes get_online_cpus(). |
cf417141 | 755 | */ |
699140ba | 756 | static void rebuild_sched_domains_locked(void) |
cf417141 MK |
757 | { |
758 | struct sched_domain_attr *attr; | |
acc3f5d7 | 759 | cpumask_var_t *doms; |
cf417141 MK |
760 | int ndoms; |
761 | ||
5d21cc2d | 762 | lockdep_assert_held(&cpuset_mutex); |
86ef5c9a | 763 | get_online_cpus(); |
cf417141 | 764 | |
5b16c2a4 LZ |
765 | /* |
766 | * We have raced with CPU hotplug. Don't do anything to avoid | |
767 | * passing doms with offlined cpu to partition_sched_domains(). | |
768 | * Anyways, hotplug work item will rebuild sched domains. | |
769 | */ | |
770 | if (!cpumask_equal(top_cpuset.cpus_allowed, cpu_active_mask)) | |
771 | goto out; | |
772 | ||
cf417141 | 773 | /* Generate domain masks and attrs */ |
cf417141 | 774 | ndoms = generate_sched_domains(&doms, &attr); |
cf417141 MK |
775 | |
776 | /* Have scheduler rebuild the domains */ | |
777 | partition_sched_domains(ndoms, doms, attr); | |
5b16c2a4 | 778 | out: |
86ef5c9a | 779 | put_online_cpus(); |
cf417141 | 780 | } |
db7f47cf | 781 | #else /* !CONFIG_SMP */ |
699140ba | 782 | static void rebuild_sched_domains_locked(void) |
db7f47cf PM |
783 | { |
784 | } | |
db7f47cf | 785 | #endif /* CONFIG_SMP */ |
029190c5 | 786 | |
cf417141 MK |
787 | void rebuild_sched_domains(void) |
788 | { | |
5d21cc2d | 789 | mutex_lock(&cpuset_mutex); |
699140ba | 790 | rebuild_sched_domains_locked(); |
5d21cc2d | 791 | mutex_unlock(&cpuset_mutex); |
029190c5 PJ |
792 | } |
793 | ||
070b57fc LZ |
794 | /* |
795 | * effective_cpumask_cpuset - return nearest ancestor with non-empty cpus | |
796 | * @cs: the cpuset in interest | |
58f4790b | 797 | * |
070b57fc LZ |
798 | * A cpuset's effective cpumask is the cpumask of the nearest ancestor |
799 | * with non-empty cpus. We use effective cpumask whenever: | |
800 | * - we update tasks' cpus_allowed. (they take on the ancestor's cpumask | |
801 | * if the cpuset they reside in has no cpus) | |
802 | * - we want to retrieve task_cs(tsk)'s cpus_allowed. | |
803 | * | |
804 | * Called with cpuset_mutex held. cpuset_cpus_allowed_fallback() is an | |
805 | * exception. See comments there. | |
806 | */ | |
807 | static struct cpuset *effective_cpumask_cpuset(struct cpuset *cs) | |
808 | { | |
809 | while (cpumask_empty(cs->cpus_allowed)) | |
810 | cs = parent_cs(cs); | |
811 | return cs; | |
812 | } | |
813 | ||
814 | /* | |
815 | * effective_nodemask_cpuset - return nearest ancestor with non-empty mems | |
816 | * @cs: the cpuset in interest | |
817 | * | |
818 | * A cpuset's effective nodemask is the nodemask of the nearest ancestor | |
819 | * with non-empty memss. We use effective nodemask whenever: | |
820 | * - we update tasks' mems_allowed. (they take on the ancestor's nodemask | |
821 | * if the cpuset they reside in has no mems) | |
822 | * - we want to retrieve task_cs(tsk)'s mems_allowed. | |
823 | * | |
824 | * Called with cpuset_mutex held. | |
053199ed | 825 | */ |
070b57fc | 826 | static struct cpuset *effective_nodemask_cpuset(struct cpuset *cs) |
58f4790b | 827 | { |
070b57fc LZ |
828 | while (nodes_empty(cs->mems_allowed)) |
829 | cs = parent_cs(cs); | |
830 | return cs; | |
58f4790b | 831 | } |
053199ed | 832 | |
58f4790b CW |
833 | /** |
834 | * cpuset_change_cpumask - make a task's cpus_allowed the same as its cpuset's | |
835 | * @tsk: task to test | |
836 | * @scan: struct cgroup_scanner containing the cgroup of the task | |
837 | * | |
838 | * Called by cgroup_scan_tasks() for each task in a cgroup whose | |
839 | * cpus_allowed mask needs to be changed. | |
840 | * | |
841 | * We don't need to re-check for the cgroup/cpuset membership, since we're | |
5d21cc2d | 842 | * holding cpuset_mutex at this point. |
58f4790b | 843 | */ |
9e0c914c AB |
844 | static void cpuset_change_cpumask(struct task_struct *tsk, |
845 | struct cgroup_scanner *scan) | |
58f4790b | 846 | { |
070b57fc LZ |
847 | struct cpuset *cpus_cs; |
848 | ||
849 | cpus_cs = effective_cpumask_cpuset(cgroup_cs(scan->cg)); | |
850 | set_cpus_allowed_ptr(tsk, cpus_cs->cpus_allowed); | |
58f4790b CW |
851 | } |
852 | ||
0b2f630a MX |
853 | /** |
854 | * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset. | |
855 | * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed | |
4e74339a | 856 | * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks() |
0b2f630a | 857 | * |
5d21cc2d | 858 | * Called with cpuset_mutex held |
0b2f630a MX |
859 | * |
860 | * The cgroup_scan_tasks() function will scan all the tasks in a cgroup, | |
861 | * calling callback functions for each. | |
862 | * | |
4e74339a LZ |
863 | * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0 |
864 | * if @heap != NULL. | |
0b2f630a | 865 | */ |
4e74339a | 866 | static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap) |
0b2f630a MX |
867 | { |
868 | struct cgroup_scanner scan; | |
0b2f630a MX |
869 | |
870 | scan.cg = cs->css.cgroup; | |
249cc86d | 871 | scan.test_task = NULL; |
0b2f630a | 872 | scan.process_task = cpuset_change_cpumask; |
4e74339a LZ |
873 | scan.heap = heap; |
874 | cgroup_scan_tasks(&scan); | |
0b2f630a MX |
875 | } |
876 | ||
5c5cc623 LZ |
877 | /* |
878 | * update_tasks_cpumask_hier - Update the cpumasks of tasks in the hierarchy. | |
879 | * @root_cs: the root cpuset of the hierarchy | |
880 | * @update_root: update root cpuset or not? | |
881 | * @heap: the heap used by cgroup_scan_tasks() | |
882 | * | |
883 | * This will update cpumasks of tasks in @root_cs and all other empty cpusets | |
884 | * which take on cpumask of @root_cs. | |
885 | * | |
886 | * Called with cpuset_mutex held | |
887 | */ | |
888 | static void update_tasks_cpumask_hier(struct cpuset *root_cs, | |
889 | bool update_root, struct ptr_heap *heap) | |
890 | { | |
891 | struct cpuset *cp; | |
892 | struct cgroup *pos_cgrp; | |
893 | ||
894 | if (update_root) | |
895 | update_tasks_cpumask(root_cs, heap); | |
896 | ||
897 | rcu_read_lock(); | |
898 | cpuset_for_each_descendant_pre(cp, pos_cgrp, root_cs) { | |
899 | /* skip the whole subtree if @cp have some CPU */ | |
900 | if (!cpumask_empty(cp->cpus_allowed)) { | |
901 | pos_cgrp = cgroup_rightmost_descendant(pos_cgrp); | |
902 | continue; | |
903 | } | |
904 | if (!css_tryget(&cp->css)) | |
905 | continue; | |
906 | rcu_read_unlock(); | |
907 | ||
908 | update_tasks_cpumask(cp, heap); | |
909 | ||
910 | rcu_read_lock(); | |
911 | css_put(&cp->css); | |
912 | } | |
913 | rcu_read_unlock(); | |
914 | } | |
915 | ||
58f4790b CW |
916 | /** |
917 | * update_cpumask - update the cpus_allowed mask of a cpuset and all tasks in it | |
918 | * @cs: the cpuset to consider | |
919 | * @buf: buffer of cpu numbers written to this cpuset | |
920 | */ | |
645fcc9d LZ |
921 | static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, |
922 | const char *buf) | |
1da177e4 | 923 | { |
4e74339a | 924 | struct ptr_heap heap; |
58f4790b CW |
925 | int retval; |
926 | int is_load_balanced; | |
1da177e4 | 927 | |
5f054e31 | 928 | /* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */ |
4c4d50f7 PJ |
929 | if (cs == &top_cpuset) |
930 | return -EACCES; | |
931 | ||
6f7f02e7 | 932 | /* |
c8d9c90c | 933 | * An empty cpus_allowed is ok only if the cpuset has no tasks. |
020958b6 PJ |
934 | * Since cpulist_parse() fails on an empty mask, we special case |
935 | * that parsing. The validate_change() call ensures that cpusets | |
936 | * with tasks have cpus. | |
6f7f02e7 | 937 | */ |
020958b6 | 938 | if (!*buf) { |
300ed6cb | 939 | cpumask_clear(trialcs->cpus_allowed); |
6f7f02e7 | 940 | } else { |
300ed6cb | 941 | retval = cpulist_parse(buf, trialcs->cpus_allowed); |
6f7f02e7 DR |
942 | if (retval < 0) |
943 | return retval; | |
37340746 | 944 | |
6ad4c188 | 945 | if (!cpumask_subset(trialcs->cpus_allowed, cpu_active_mask)) |
37340746 | 946 | return -EINVAL; |
6f7f02e7 | 947 | } |
029190c5 | 948 | |
8707d8b8 | 949 | /* Nothing to do if the cpus didn't change */ |
300ed6cb | 950 | if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed)) |
8707d8b8 | 951 | return 0; |
58f4790b | 952 | |
a73456f3 LZ |
953 | retval = validate_change(cs, trialcs); |
954 | if (retval < 0) | |
955 | return retval; | |
956 | ||
4e74339a LZ |
957 | retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); |
958 | if (retval) | |
959 | return retval; | |
960 | ||
645fcc9d | 961 | is_load_balanced = is_sched_load_balance(trialcs); |
029190c5 | 962 | |
3d3f26a7 | 963 | mutex_lock(&callback_mutex); |
300ed6cb | 964 | cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed); |
3d3f26a7 | 965 | mutex_unlock(&callback_mutex); |
029190c5 | 966 | |
5c5cc623 | 967 | update_tasks_cpumask_hier(cs, true, &heap); |
4e74339a LZ |
968 | |
969 | heap_free(&heap); | |
58f4790b | 970 | |
8707d8b8 | 971 | if (is_load_balanced) |
699140ba | 972 | rebuild_sched_domains_locked(); |
85d7b949 | 973 | return 0; |
1da177e4 LT |
974 | } |
975 | ||
e4e364e8 PJ |
976 | /* |
977 | * cpuset_migrate_mm | |
978 | * | |
979 | * Migrate memory region from one set of nodes to another. | |
980 | * | |
981 | * Temporarilly set tasks mems_allowed to target nodes of migration, | |
982 | * so that the migration code can allocate pages on these nodes. | |
983 | * | |
5d21cc2d | 984 | * Call holding cpuset_mutex, so current's cpuset won't change |
c8d9c90c | 985 | * during this call, as manage_mutex holds off any cpuset_attach() |
e4e364e8 PJ |
986 | * calls. Therefore we don't need to take task_lock around the |
987 | * call to guarantee_online_mems(), as we know no one is changing | |
2df167a3 | 988 | * our task's cpuset. |
e4e364e8 | 989 | * |
e4e364e8 PJ |
990 | * While the mm_struct we are migrating is typically from some |
991 | * other task, the task_struct mems_allowed that we are hacking | |
992 | * is for our current task, which must allocate new pages for that | |
993 | * migrating memory region. | |
e4e364e8 PJ |
994 | */ |
995 | ||
996 | static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from, | |
997 | const nodemask_t *to) | |
998 | { | |
999 | struct task_struct *tsk = current; | |
070b57fc | 1000 | struct cpuset *mems_cs; |
e4e364e8 | 1001 | |
e4e364e8 | 1002 | tsk->mems_allowed = *to; |
e4e364e8 PJ |
1003 | |
1004 | do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL); | |
1005 | ||
070b57fc LZ |
1006 | mems_cs = effective_nodemask_cpuset(task_cs(tsk)); |
1007 | guarantee_online_mems(mems_cs, &tsk->mems_allowed); | |
e4e364e8 PJ |
1008 | } |
1009 | ||
3b6766fe | 1010 | /* |
58568d2a MX |
1011 | * cpuset_change_task_nodemask - change task's mems_allowed and mempolicy |
1012 | * @tsk: the task to change | |
1013 | * @newmems: new nodes that the task will be set | |
1014 | * | |
1015 | * In order to avoid seeing no nodes if the old and new nodes are disjoint, | |
1016 | * we structure updates as setting all new allowed nodes, then clearing newly | |
1017 | * disallowed ones. | |
58568d2a MX |
1018 | */ |
1019 | static void cpuset_change_task_nodemask(struct task_struct *tsk, | |
1020 | nodemask_t *newmems) | |
1021 | { | |
b246272e | 1022 | bool need_loop; |
89e8a244 | 1023 | |
c0ff7453 MX |
1024 | /* |
1025 | * Allow tasks that have access to memory reserves because they have | |
1026 | * been OOM killed to get memory anywhere. | |
1027 | */ | |
1028 | if (unlikely(test_thread_flag(TIF_MEMDIE))) | |
1029 | return; | |
1030 | if (current->flags & PF_EXITING) /* Let dying task have memory */ | |
1031 | return; | |
1032 | ||
1033 | task_lock(tsk); | |
b246272e DR |
1034 | /* |
1035 | * Determine if a loop is necessary if another thread is doing | |
1036 | * get_mems_allowed(). If at least one node remains unchanged and | |
1037 | * tsk does not have a mempolicy, then an empty nodemask will not be | |
1038 | * possible when mems_allowed is larger than a word. | |
1039 | */ | |
1040 | need_loop = task_has_mempolicy(tsk) || | |
1041 | !nodes_intersects(*newmems, tsk->mems_allowed); | |
c0ff7453 | 1042 | |
cc9a6c87 MG |
1043 | if (need_loop) |
1044 | write_seqcount_begin(&tsk->mems_allowed_seq); | |
c0ff7453 | 1045 | |
cc9a6c87 MG |
1046 | nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems); |
1047 | mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1); | |
c0ff7453 MX |
1048 | |
1049 | mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP2); | |
58568d2a | 1050 | tsk->mems_allowed = *newmems; |
cc9a6c87 MG |
1051 | |
1052 | if (need_loop) | |
1053 | write_seqcount_end(&tsk->mems_allowed_seq); | |
1054 | ||
c0ff7453 | 1055 | task_unlock(tsk); |
58568d2a MX |
1056 | } |
1057 | ||
1058 | /* | |
1059 | * Update task's mems_allowed and rebind its mempolicy and vmas' mempolicy | |
1060 | * of it to cpuset's new mems_allowed, and migrate pages to new nodes if | |
5d21cc2d | 1061 | * memory_migrate flag is set. Called with cpuset_mutex held. |
3b6766fe LZ |
1062 | */ |
1063 | static void cpuset_change_nodemask(struct task_struct *p, | |
1064 | struct cgroup_scanner *scan) | |
1065 | { | |
33ad801d | 1066 | struct cpuset *cs = cgroup_cs(scan->cg); |
3b6766fe | 1067 | struct mm_struct *mm; |
3b6766fe | 1068 | int migrate; |
33ad801d | 1069 | nodemask_t *newmems = scan->data; |
58568d2a | 1070 | |
33ad801d | 1071 | cpuset_change_task_nodemask(p, newmems); |
53feb297 | 1072 | |
3b6766fe LZ |
1073 | mm = get_task_mm(p); |
1074 | if (!mm) | |
1075 | return; | |
1076 | ||
3b6766fe LZ |
1077 | migrate = is_memory_migrate(cs); |
1078 | ||
1079 | mpol_rebind_mm(mm, &cs->mems_allowed); | |
1080 | if (migrate) | |
33ad801d | 1081 | cpuset_migrate_mm(mm, &cs->old_mems_allowed, newmems); |
3b6766fe LZ |
1082 | mmput(mm); |
1083 | } | |
1084 | ||
8793d854 PM |
1085 | static void *cpuset_being_rebound; |
1086 | ||
0b2f630a MX |
1087 | /** |
1088 | * update_tasks_nodemask - Update the nodemasks of tasks in the cpuset. | |
1089 | * @cs: the cpuset in which each task's mems_allowed mask needs to be changed | |
010cfac4 | 1090 | * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks() |
0b2f630a | 1091 | * |
5d21cc2d | 1092 | * Called with cpuset_mutex held |
010cfac4 LZ |
1093 | * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0 |
1094 | * if @heap != NULL. | |
0b2f630a | 1095 | */ |
33ad801d | 1096 | static void update_tasks_nodemask(struct cpuset *cs, struct ptr_heap *heap) |
1da177e4 | 1097 | { |
33ad801d | 1098 | static nodemask_t newmems; /* protected by cpuset_mutex */ |
3b6766fe | 1099 | struct cgroup_scanner scan; |
070b57fc | 1100 | struct cpuset *mems_cs = effective_nodemask_cpuset(cs); |
59dac16f | 1101 | |
846a16bf | 1102 | cpuset_being_rebound = cs; /* causes mpol_dup() rebind */ |
4225399a | 1103 | |
070b57fc | 1104 | guarantee_online_mems(mems_cs, &newmems); |
33ad801d | 1105 | |
3b6766fe LZ |
1106 | scan.cg = cs->css.cgroup; |
1107 | scan.test_task = NULL; | |
1108 | scan.process_task = cpuset_change_nodemask; | |
010cfac4 | 1109 | scan.heap = heap; |
33ad801d | 1110 | scan.data = &newmems; |
4225399a PJ |
1111 | |
1112 | /* | |
3b6766fe LZ |
1113 | * The mpol_rebind_mm() call takes mmap_sem, which we couldn't |
1114 | * take while holding tasklist_lock. Forks can happen - the | |
1115 | * mpol_dup() cpuset_being_rebound check will catch such forks, | |
1116 | * and rebind their vma mempolicies too. Because we still hold | |
5d21cc2d | 1117 | * the global cpuset_mutex, we know that no other rebind effort |
3b6766fe | 1118 | * will be contending for the global variable cpuset_being_rebound. |
4225399a | 1119 | * It's ok if we rebind the same mm twice; mpol_rebind_mm() |
04c19fa6 | 1120 | * is idempotent. Also migrate pages in each mm to new nodes. |
4225399a | 1121 | */ |
010cfac4 | 1122 | cgroup_scan_tasks(&scan); |
4225399a | 1123 | |
33ad801d LZ |
1124 | /* |
1125 | * All the tasks' nodemasks have been updated, update | |
1126 | * cs->old_mems_allowed. | |
1127 | */ | |
1128 | cs->old_mems_allowed = newmems; | |
1129 | ||
2df167a3 | 1130 | /* We're done rebinding vmas to this cpuset's new mems_allowed. */ |
8793d854 | 1131 | cpuset_being_rebound = NULL; |
1da177e4 LT |
1132 | } |
1133 | ||
5c5cc623 LZ |
1134 | /* |
1135 | * update_tasks_nodemask_hier - Update the nodemasks of tasks in the hierarchy. | |
1136 | * @cs: the root cpuset of the hierarchy | |
1137 | * @update_root: update the root cpuset or not? | |
1138 | * @heap: the heap used by cgroup_scan_tasks() | |
1139 | * | |
1140 | * This will update nodemasks of tasks in @root_cs and all other empty cpusets | |
1141 | * which take on nodemask of @root_cs. | |
1142 | * | |
1143 | * Called with cpuset_mutex held | |
1144 | */ | |
1145 | static void update_tasks_nodemask_hier(struct cpuset *root_cs, | |
1146 | bool update_root, struct ptr_heap *heap) | |
1147 | { | |
1148 | struct cpuset *cp; | |
1149 | struct cgroup *pos_cgrp; | |
1150 | ||
1151 | if (update_root) | |
1152 | update_tasks_nodemask(root_cs, heap); | |
1153 | ||
1154 | rcu_read_lock(); | |
1155 | cpuset_for_each_descendant_pre(cp, pos_cgrp, root_cs) { | |
1156 | /* skip the whole subtree if @cp have some CPU */ | |
1157 | if (!nodes_empty(cp->mems_allowed)) { | |
1158 | pos_cgrp = cgroup_rightmost_descendant(pos_cgrp); | |
1159 | continue; | |
1160 | } | |
1161 | if (!css_tryget(&cp->css)) | |
1162 | continue; | |
1163 | rcu_read_unlock(); | |
1164 | ||
1165 | update_tasks_nodemask(cp, heap); | |
1166 | ||
1167 | rcu_read_lock(); | |
1168 | css_put(&cp->css); | |
1169 | } | |
1170 | rcu_read_unlock(); | |
1171 | } | |
1172 | ||
0b2f630a MX |
1173 | /* |
1174 | * Handle user request to change the 'mems' memory placement | |
1175 | * of a cpuset. Needs to validate the request, update the | |
58568d2a MX |
1176 | * cpusets mems_allowed, and for each task in the cpuset, |
1177 | * update mems_allowed and rebind task's mempolicy and any vma | |
1178 | * mempolicies and if the cpuset is marked 'memory_migrate', | |
1179 | * migrate the tasks pages to the new memory. | |
0b2f630a | 1180 | * |
5d21cc2d | 1181 | * Call with cpuset_mutex held. May take callback_mutex during call. |
0b2f630a MX |
1182 | * Will take tasklist_lock, scan tasklist for tasks in cpuset cs, |
1183 | * lock each such tasks mm->mmap_sem, scan its vma's and rebind | |
1184 | * their mempolicies to the cpusets new mems_allowed. | |
1185 | */ | |
645fcc9d LZ |
1186 | static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs, |
1187 | const char *buf) | |
0b2f630a | 1188 | { |
0b2f630a | 1189 | int retval; |
010cfac4 | 1190 | struct ptr_heap heap; |
0b2f630a MX |
1191 | |
1192 | /* | |
38d7bee9 | 1193 | * top_cpuset.mems_allowed tracks node_stats[N_MEMORY]; |
0b2f630a MX |
1194 | * it's read-only |
1195 | */ | |
53feb297 MX |
1196 | if (cs == &top_cpuset) { |
1197 | retval = -EACCES; | |
1198 | goto done; | |
1199 | } | |
0b2f630a | 1200 | |
0b2f630a MX |
1201 | /* |
1202 | * An empty mems_allowed is ok iff there are no tasks in the cpuset. | |
1203 | * Since nodelist_parse() fails on an empty mask, we special case | |
1204 | * that parsing. The validate_change() call ensures that cpusets | |
1205 | * with tasks have memory. | |
1206 | */ | |
1207 | if (!*buf) { | |
645fcc9d | 1208 | nodes_clear(trialcs->mems_allowed); |
0b2f630a | 1209 | } else { |
645fcc9d | 1210 | retval = nodelist_parse(buf, trialcs->mems_allowed); |
0b2f630a MX |
1211 | if (retval < 0) |
1212 | goto done; | |
1213 | ||
645fcc9d | 1214 | if (!nodes_subset(trialcs->mems_allowed, |
38d7bee9 | 1215 | node_states[N_MEMORY])) { |
53feb297 MX |
1216 | retval = -EINVAL; |
1217 | goto done; | |
1218 | } | |
0b2f630a | 1219 | } |
33ad801d LZ |
1220 | |
1221 | if (nodes_equal(cs->mems_allowed, trialcs->mems_allowed)) { | |
0b2f630a MX |
1222 | retval = 0; /* Too easy - nothing to do */ |
1223 | goto done; | |
1224 | } | |
645fcc9d | 1225 | retval = validate_change(cs, trialcs); |
0b2f630a MX |
1226 | if (retval < 0) |
1227 | goto done; | |
1228 | ||
010cfac4 LZ |
1229 | retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); |
1230 | if (retval < 0) | |
1231 | goto done; | |
1232 | ||
0b2f630a | 1233 | mutex_lock(&callback_mutex); |
645fcc9d | 1234 | cs->mems_allowed = trialcs->mems_allowed; |
0b2f630a MX |
1235 | mutex_unlock(&callback_mutex); |
1236 | ||
5c5cc623 | 1237 | update_tasks_nodemask_hier(cs, true, &heap); |
010cfac4 LZ |
1238 | |
1239 | heap_free(&heap); | |
0b2f630a MX |
1240 | done: |
1241 | return retval; | |
1242 | } | |
1243 | ||
8793d854 PM |
1244 | int current_cpuset_is_being_rebound(void) |
1245 | { | |
1246 | return task_cs(current) == cpuset_being_rebound; | |
1247 | } | |
1248 | ||
5be7a479 | 1249 | static int update_relax_domain_level(struct cpuset *cs, s64 val) |
1d3504fc | 1250 | { |
db7f47cf | 1251 | #ifdef CONFIG_SMP |
60495e77 | 1252 | if (val < -1 || val >= sched_domain_level_max) |
30e0e178 | 1253 | return -EINVAL; |
db7f47cf | 1254 | #endif |
1d3504fc HS |
1255 | |
1256 | if (val != cs->relax_domain_level) { | |
1257 | cs->relax_domain_level = val; | |
300ed6cb LZ |
1258 | if (!cpumask_empty(cs->cpus_allowed) && |
1259 | is_sched_load_balance(cs)) | |
699140ba | 1260 | rebuild_sched_domains_locked(); |
1d3504fc HS |
1261 | } |
1262 | ||
1263 | return 0; | |
1264 | } | |
1265 | ||
950592f7 MX |
1266 | /* |
1267 | * cpuset_change_flag - make a task's spread flags the same as its cpuset's | |
1268 | * @tsk: task to be updated | |
1269 | * @scan: struct cgroup_scanner containing the cgroup of the task | |
1270 | * | |
1271 | * Called by cgroup_scan_tasks() for each task in a cgroup. | |
1272 | * | |
1273 | * We don't need to re-check for the cgroup/cpuset membership, since we're | |
5d21cc2d | 1274 | * holding cpuset_mutex at this point. |
950592f7 MX |
1275 | */ |
1276 | static void cpuset_change_flag(struct task_struct *tsk, | |
1277 | struct cgroup_scanner *scan) | |
1278 | { | |
1279 | cpuset_update_task_spread_flag(cgroup_cs(scan->cg), tsk); | |
1280 | } | |
1281 | ||
1282 | /* | |
1283 | * update_tasks_flags - update the spread flags of tasks in the cpuset. | |
1284 | * @cs: the cpuset in which each task's spread flags needs to be changed | |
1285 | * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks() | |
1286 | * | |
5d21cc2d | 1287 | * Called with cpuset_mutex held |
950592f7 MX |
1288 | * |
1289 | * The cgroup_scan_tasks() function will scan all the tasks in a cgroup, | |
1290 | * calling callback functions for each. | |
1291 | * | |
1292 | * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0 | |
1293 | * if @heap != NULL. | |
1294 | */ | |
1295 | static void update_tasks_flags(struct cpuset *cs, struct ptr_heap *heap) | |
1296 | { | |
1297 | struct cgroup_scanner scan; | |
1298 | ||
1299 | scan.cg = cs->css.cgroup; | |
1300 | scan.test_task = NULL; | |
1301 | scan.process_task = cpuset_change_flag; | |
1302 | scan.heap = heap; | |
1303 | cgroup_scan_tasks(&scan); | |
1304 | } | |
1305 | ||
1da177e4 LT |
1306 | /* |
1307 | * update_flag - read a 0 or a 1 in a file and update associated flag | |
78608366 PM |
1308 | * bit: the bit to update (see cpuset_flagbits_t) |
1309 | * cs: the cpuset to update | |
1310 | * turning_on: whether the flag is being set or cleared | |
053199ed | 1311 | * |
5d21cc2d | 1312 | * Call with cpuset_mutex held. |
1da177e4 LT |
1313 | */ |
1314 | ||
700fe1ab PM |
1315 | static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, |
1316 | int turning_on) | |
1da177e4 | 1317 | { |
645fcc9d | 1318 | struct cpuset *trialcs; |
40b6a762 | 1319 | int balance_flag_changed; |
950592f7 MX |
1320 | int spread_flag_changed; |
1321 | struct ptr_heap heap; | |
1322 | int err; | |
1da177e4 | 1323 | |
645fcc9d LZ |
1324 | trialcs = alloc_trial_cpuset(cs); |
1325 | if (!trialcs) | |
1326 | return -ENOMEM; | |
1327 | ||
1da177e4 | 1328 | if (turning_on) |
645fcc9d | 1329 | set_bit(bit, &trialcs->flags); |
1da177e4 | 1330 | else |
645fcc9d | 1331 | clear_bit(bit, &trialcs->flags); |
1da177e4 | 1332 | |
645fcc9d | 1333 | err = validate_change(cs, trialcs); |
85d7b949 | 1334 | if (err < 0) |
645fcc9d | 1335 | goto out; |
029190c5 | 1336 | |
950592f7 MX |
1337 | err = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); |
1338 | if (err < 0) | |
1339 | goto out; | |
1340 | ||
029190c5 | 1341 | balance_flag_changed = (is_sched_load_balance(cs) != |
645fcc9d | 1342 | is_sched_load_balance(trialcs)); |
029190c5 | 1343 | |
950592f7 MX |
1344 | spread_flag_changed = ((is_spread_slab(cs) != is_spread_slab(trialcs)) |
1345 | || (is_spread_page(cs) != is_spread_page(trialcs))); | |
1346 | ||
3d3f26a7 | 1347 | mutex_lock(&callback_mutex); |
645fcc9d | 1348 | cs->flags = trialcs->flags; |
3d3f26a7 | 1349 | mutex_unlock(&callback_mutex); |
85d7b949 | 1350 | |
300ed6cb | 1351 | if (!cpumask_empty(trialcs->cpus_allowed) && balance_flag_changed) |
699140ba | 1352 | rebuild_sched_domains_locked(); |
029190c5 | 1353 | |
950592f7 MX |
1354 | if (spread_flag_changed) |
1355 | update_tasks_flags(cs, &heap); | |
1356 | heap_free(&heap); | |
645fcc9d LZ |
1357 | out: |
1358 | free_trial_cpuset(trialcs); | |
1359 | return err; | |
1da177e4 LT |
1360 | } |
1361 | ||
3e0d98b9 | 1362 | /* |
80f7228b | 1363 | * Frequency meter - How fast is some event occurring? |
3e0d98b9 PJ |
1364 | * |
1365 | * These routines manage a digitally filtered, constant time based, | |
1366 | * event frequency meter. There are four routines: | |
1367 | * fmeter_init() - initialize a frequency meter. | |
1368 | * fmeter_markevent() - called each time the event happens. | |
1369 | * fmeter_getrate() - returns the recent rate of such events. | |
1370 | * fmeter_update() - internal routine used to update fmeter. | |
1371 | * | |
1372 | * A common data structure is passed to each of these routines, | |
1373 | * which is used to keep track of the state required to manage the | |
1374 | * frequency meter and its digital filter. | |
1375 | * | |
1376 | * The filter works on the number of events marked per unit time. | |
1377 | * The filter is single-pole low-pass recursive (IIR). The time unit | |
1378 | * is 1 second. Arithmetic is done using 32-bit integers scaled to | |
1379 | * simulate 3 decimal digits of precision (multiplied by 1000). | |
1380 | * | |
1381 | * With an FM_COEF of 933, and a time base of 1 second, the filter | |
1382 | * has a half-life of 10 seconds, meaning that if the events quit | |
1383 | * happening, then the rate returned from the fmeter_getrate() | |
1384 | * will be cut in half each 10 seconds, until it converges to zero. | |
1385 | * | |
1386 | * It is not worth doing a real infinitely recursive filter. If more | |
1387 | * than FM_MAXTICKS ticks have elapsed since the last filter event, | |
1388 | * just compute FM_MAXTICKS ticks worth, by which point the level | |
1389 | * will be stable. | |
1390 | * | |
1391 | * Limit the count of unprocessed events to FM_MAXCNT, so as to avoid | |
1392 | * arithmetic overflow in the fmeter_update() routine. | |
1393 | * | |
1394 | * Given the simple 32 bit integer arithmetic used, this meter works | |
1395 | * best for reporting rates between one per millisecond (msec) and | |
1396 | * one per 32 (approx) seconds. At constant rates faster than one | |
1397 | * per msec it maxes out at values just under 1,000,000. At constant | |
1398 | * rates between one per msec, and one per second it will stabilize | |
1399 | * to a value N*1000, where N is the rate of events per second. | |
1400 | * At constant rates between one per second and one per 32 seconds, | |
1401 | * it will be choppy, moving up on the seconds that have an event, | |
1402 | * and then decaying until the next event. At rates slower than | |
1403 | * about one in 32 seconds, it decays all the way back to zero between | |
1404 | * each event. | |
1405 | */ | |
1406 | ||
1407 | #define FM_COEF 933 /* coefficient for half-life of 10 secs */ | |
1408 | #define FM_MAXTICKS ((time_t)99) /* useless computing more ticks than this */ | |
1409 | #define FM_MAXCNT 1000000 /* limit cnt to avoid overflow */ | |
1410 | #define FM_SCALE 1000 /* faux fixed point scale */ | |
1411 | ||
1412 | /* Initialize a frequency meter */ | |
1413 | static void fmeter_init(struct fmeter *fmp) | |
1414 | { | |
1415 | fmp->cnt = 0; | |
1416 | fmp->val = 0; | |
1417 | fmp->time = 0; | |
1418 | spin_lock_init(&fmp->lock); | |
1419 | } | |
1420 | ||
1421 | /* Internal meter update - process cnt events and update value */ | |
1422 | static void fmeter_update(struct fmeter *fmp) | |
1423 | { | |
1424 | time_t now = get_seconds(); | |
1425 | time_t ticks = now - fmp->time; | |
1426 | ||
1427 | if (ticks == 0) | |
1428 | return; | |
1429 | ||
1430 | ticks = min(FM_MAXTICKS, ticks); | |
1431 | while (ticks-- > 0) | |
1432 | fmp->val = (FM_COEF * fmp->val) / FM_SCALE; | |
1433 | fmp->time = now; | |
1434 | ||
1435 | fmp->val += ((FM_SCALE - FM_COEF) * fmp->cnt) / FM_SCALE; | |
1436 | fmp->cnt = 0; | |
1437 | } | |
1438 | ||
1439 | /* Process any previous ticks, then bump cnt by one (times scale). */ | |
1440 | static void fmeter_markevent(struct fmeter *fmp) | |
1441 | { | |
1442 | spin_lock(&fmp->lock); | |
1443 | fmeter_update(fmp); | |
1444 | fmp->cnt = min(FM_MAXCNT, fmp->cnt + FM_SCALE); | |
1445 | spin_unlock(&fmp->lock); | |
1446 | } | |
1447 | ||
1448 | /* Process any previous ticks, then return current value. */ | |
1449 | static int fmeter_getrate(struct fmeter *fmp) | |
1450 | { | |
1451 | int val; | |
1452 | ||
1453 | spin_lock(&fmp->lock); | |
1454 | fmeter_update(fmp); | |
1455 | val = fmp->val; | |
1456 | spin_unlock(&fmp->lock); | |
1457 | return val; | |
1458 | } | |
1459 | ||
5d21cc2d | 1460 | /* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */ |
761b3ef5 | 1461 | static int cpuset_can_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) |
f780bdb7 | 1462 | { |
2f7ee569 | 1463 | struct cpuset *cs = cgroup_cs(cgrp); |
bb9d97b6 TH |
1464 | struct task_struct *task; |
1465 | int ret; | |
1da177e4 | 1466 | |
5d21cc2d TH |
1467 | mutex_lock(&cpuset_mutex); |
1468 | ||
88fa523b LZ |
1469 | /* |
1470 | * We allow to move tasks into an empty cpuset if sane_behavior | |
1471 | * flag is set. | |
1472 | */ | |
5d21cc2d | 1473 | ret = -ENOSPC; |
88fa523b LZ |
1474 | if (!cgroup_sane_behavior(cgrp) && |
1475 | (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))) | |
5d21cc2d | 1476 | goto out_unlock; |
9985b0ba | 1477 | |
bb9d97b6 TH |
1478 | cgroup_taskset_for_each(task, cgrp, tset) { |
1479 | /* | |
14a40ffc TH |
1480 | * Kthreads which disallow setaffinity shouldn't be moved |
1481 | * to a new cpuset; we don't want to change their cpu | |
1482 | * affinity and isolating such threads by their set of | |
1483 | * allowed nodes is unnecessary. Thus, cpusets are not | |
1484 | * applicable for such threads. This prevents checking for | |
1485 | * success of set_cpus_allowed_ptr() on all attached tasks | |
1486 | * before cpus_allowed may be changed. | |
bb9d97b6 | 1487 | */ |
5d21cc2d | 1488 | ret = -EINVAL; |
14a40ffc | 1489 | if (task->flags & PF_NO_SETAFFINITY) |
5d21cc2d TH |
1490 | goto out_unlock; |
1491 | ret = security_task_setscheduler(task); | |
1492 | if (ret) | |
1493 | goto out_unlock; | |
bb9d97b6 | 1494 | } |
f780bdb7 | 1495 | |
452477fa TH |
1496 | /* |
1497 | * Mark attach is in progress. This makes validate_change() fail | |
1498 | * changes which zero cpus/mems_allowed. | |
1499 | */ | |
1500 | cs->attach_in_progress++; | |
5d21cc2d TH |
1501 | ret = 0; |
1502 | out_unlock: | |
1503 | mutex_unlock(&cpuset_mutex); | |
1504 | return ret; | |
8793d854 | 1505 | } |
f780bdb7 | 1506 | |
452477fa TH |
1507 | static void cpuset_cancel_attach(struct cgroup *cgrp, |
1508 | struct cgroup_taskset *tset) | |
1509 | { | |
5d21cc2d | 1510 | mutex_lock(&cpuset_mutex); |
452477fa | 1511 | cgroup_cs(cgrp)->attach_in_progress--; |
5d21cc2d | 1512 | mutex_unlock(&cpuset_mutex); |
8793d854 | 1513 | } |
1da177e4 | 1514 | |
4e4c9a14 | 1515 | /* |
5d21cc2d | 1516 | * Protected by cpuset_mutex. cpus_attach is used only by cpuset_attach() |
4e4c9a14 TH |
1517 | * but we can't allocate it dynamically there. Define it global and |
1518 | * allocate from cpuset_init(). | |
1519 | */ | |
1520 | static cpumask_var_t cpus_attach; | |
1521 | ||
761b3ef5 | 1522 | static void cpuset_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) |
8793d854 | 1523 | { |
67bd2c59 | 1524 | /* static buf protected by cpuset_mutex */ |
4e4c9a14 | 1525 | static nodemask_t cpuset_attach_nodemask_to; |
8793d854 | 1526 | struct mm_struct *mm; |
bb9d97b6 TH |
1527 | struct task_struct *task; |
1528 | struct task_struct *leader = cgroup_taskset_first(tset); | |
2f7ee569 TH |
1529 | struct cgroup *oldcgrp = cgroup_taskset_cur_cgroup(tset); |
1530 | struct cpuset *cs = cgroup_cs(cgrp); | |
1531 | struct cpuset *oldcs = cgroup_cs(oldcgrp); | |
070b57fc LZ |
1532 | struct cpuset *cpus_cs = effective_cpumask_cpuset(cs); |
1533 | struct cpuset *mems_cs = effective_nodemask_cpuset(cs); | |
22fb52dd | 1534 | |
5d21cc2d TH |
1535 | mutex_lock(&cpuset_mutex); |
1536 | ||
4e4c9a14 TH |
1537 | /* prepare for attach */ |
1538 | if (cs == &top_cpuset) | |
1539 | cpumask_copy(cpus_attach, cpu_possible_mask); | |
1540 | else | |
070b57fc | 1541 | guarantee_online_cpus(cpus_cs, cpus_attach); |
4e4c9a14 | 1542 | |
070b57fc | 1543 | guarantee_online_mems(mems_cs, &cpuset_attach_nodemask_to); |
4e4c9a14 | 1544 | |
bb9d97b6 TH |
1545 | cgroup_taskset_for_each(task, cgrp, tset) { |
1546 | /* | |
1547 | * can_attach beforehand should guarantee that this doesn't | |
1548 | * fail. TODO: have a better way to handle failure here | |
1549 | */ | |
1550 | WARN_ON_ONCE(set_cpus_allowed_ptr(task, cpus_attach)); | |
1551 | ||
1552 | cpuset_change_task_nodemask(task, &cpuset_attach_nodemask_to); | |
1553 | cpuset_update_task_spread_flag(cs, task); | |
1554 | } | |
22fb52dd | 1555 | |
f780bdb7 BB |
1556 | /* |
1557 | * Change mm, possibly for multiple threads in a threadgroup. This is | |
1558 | * expensive and may sleep. | |
1559 | */ | |
f780bdb7 | 1560 | cpuset_attach_nodemask_to = cs->mems_allowed; |
bb9d97b6 | 1561 | mm = get_task_mm(leader); |
4225399a | 1562 | if (mm) { |
070b57fc LZ |
1563 | struct cpuset *mems_oldcs = effective_nodemask_cpuset(oldcs); |
1564 | ||
f780bdb7 | 1565 | mpol_rebind_mm(mm, &cpuset_attach_nodemask_to); |
f047cecf LZ |
1566 | |
1567 | /* | |
1568 | * old_mems_allowed is the same with mems_allowed here, except | |
1569 | * if this task is being moved automatically due to hotplug. | |
1570 | * In that case @mems_allowed has been updated and is empty, | |
1571 | * so @old_mems_allowed is the right nodesets that we migrate | |
1572 | * mm from. | |
1573 | */ | |
1574 | if (is_memory_migrate(cs)) { | |
1575 | cpuset_migrate_mm(mm, &mems_oldcs->old_mems_allowed, | |
f780bdb7 | 1576 | &cpuset_attach_nodemask_to); |
f047cecf | 1577 | } |
4225399a PJ |
1578 | mmput(mm); |
1579 | } | |
452477fa | 1580 | |
33ad801d | 1581 | cs->old_mems_allowed = cpuset_attach_nodemask_to; |
02bb5863 | 1582 | |
452477fa | 1583 | cs->attach_in_progress--; |
e44193d3 LZ |
1584 | if (!cs->attach_in_progress) |
1585 | wake_up(&cpuset_attach_wq); | |
5d21cc2d TH |
1586 | |
1587 | mutex_unlock(&cpuset_mutex); | |
1da177e4 LT |
1588 | } |
1589 | ||
1590 | /* The various types of files and directories in a cpuset file system */ | |
1591 | ||
1592 | typedef enum { | |
45b07ef3 | 1593 | FILE_MEMORY_MIGRATE, |
1da177e4 LT |
1594 | FILE_CPULIST, |
1595 | FILE_MEMLIST, | |
1596 | FILE_CPU_EXCLUSIVE, | |
1597 | FILE_MEM_EXCLUSIVE, | |
78608366 | 1598 | FILE_MEM_HARDWALL, |
029190c5 | 1599 | FILE_SCHED_LOAD_BALANCE, |
1d3504fc | 1600 | FILE_SCHED_RELAX_DOMAIN_LEVEL, |
3e0d98b9 PJ |
1601 | FILE_MEMORY_PRESSURE_ENABLED, |
1602 | FILE_MEMORY_PRESSURE, | |
825a46af PJ |
1603 | FILE_SPREAD_PAGE, |
1604 | FILE_SPREAD_SLAB, | |
1da177e4 LT |
1605 | } cpuset_filetype_t; |
1606 | ||
700fe1ab PM |
1607 | static int cpuset_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val) |
1608 | { | |
700fe1ab PM |
1609 | struct cpuset *cs = cgroup_cs(cgrp); |
1610 | cpuset_filetype_t type = cft->private; | |
5d21cc2d | 1611 | int retval = -ENODEV; |
700fe1ab | 1612 | |
5d21cc2d TH |
1613 | mutex_lock(&cpuset_mutex); |
1614 | if (!is_cpuset_online(cs)) | |
1615 | goto out_unlock; | |
700fe1ab PM |
1616 | |
1617 | switch (type) { | |
1da177e4 | 1618 | case FILE_CPU_EXCLUSIVE: |
700fe1ab | 1619 | retval = update_flag(CS_CPU_EXCLUSIVE, cs, val); |
1da177e4 LT |
1620 | break; |
1621 | case FILE_MEM_EXCLUSIVE: | |
700fe1ab | 1622 | retval = update_flag(CS_MEM_EXCLUSIVE, cs, val); |
1da177e4 | 1623 | break; |
78608366 PM |
1624 | case FILE_MEM_HARDWALL: |
1625 | retval = update_flag(CS_MEM_HARDWALL, cs, val); | |
1626 | break; | |
029190c5 | 1627 | case FILE_SCHED_LOAD_BALANCE: |
700fe1ab | 1628 | retval = update_flag(CS_SCHED_LOAD_BALANCE, cs, val); |
1d3504fc | 1629 | break; |
45b07ef3 | 1630 | case FILE_MEMORY_MIGRATE: |
700fe1ab | 1631 | retval = update_flag(CS_MEMORY_MIGRATE, cs, val); |
45b07ef3 | 1632 | break; |
3e0d98b9 | 1633 | case FILE_MEMORY_PRESSURE_ENABLED: |
700fe1ab | 1634 | cpuset_memory_pressure_enabled = !!val; |
3e0d98b9 PJ |
1635 | break; |
1636 | case FILE_MEMORY_PRESSURE: | |
1637 | retval = -EACCES; | |
1638 | break; | |
825a46af | 1639 | case FILE_SPREAD_PAGE: |
700fe1ab | 1640 | retval = update_flag(CS_SPREAD_PAGE, cs, val); |
825a46af PJ |
1641 | break; |
1642 | case FILE_SPREAD_SLAB: | |
700fe1ab | 1643 | retval = update_flag(CS_SPREAD_SLAB, cs, val); |
825a46af | 1644 | break; |
1da177e4 LT |
1645 | default: |
1646 | retval = -EINVAL; | |
700fe1ab | 1647 | break; |
1da177e4 | 1648 | } |
5d21cc2d TH |
1649 | out_unlock: |
1650 | mutex_unlock(&cpuset_mutex); | |
1da177e4 LT |
1651 | return retval; |
1652 | } | |
1653 | ||
5be7a479 PM |
1654 | static int cpuset_write_s64(struct cgroup *cgrp, struct cftype *cft, s64 val) |
1655 | { | |
5be7a479 PM |
1656 | struct cpuset *cs = cgroup_cs(cgrp); |
1657 | cpuset_filetype_t type = cft->private; | |
5d21cc2d | 1658 | int retval = -ENODEV; |
5be7a479 | 1659 | |
5d21cc2d TH |
1660 | mutex_lock(&cpuset_mutex); |
1661 | if (!is_cpuset_online(cs)) | |
1662 | goto out_unlock; | |
e3712395 | 1663 | |
5be7a479 PM |
1664 | switch (type) { |
1665 | case FILE_SCHED_RELAX_DOMAIN_LEVEL: | |
1666 | retval = update_relax_domain_level(cs, val); | |
1667 | break; | |
1668 | default: | |
1669 | retval = -EINVAL; | |
1670 | break; | |
1671 | } | |
5d21cc2d TH |
1672 | out_unlock: |
1673 | mutex_unlock(&cpuset_mutex); | |
5be7a479 PM |
1674 | return retval; |
1675 | } | |
1676 | ||
e3712395 PM |
1677 | /* |
1678 | * Common handling for a write to a "cpus" or "mems" file. | |
1679 | */ | |
1680 | static int cpuset_write_resmask(struct cgroup *cgrp, struct cftype *cft, | |
1681 | const char *buf) | |
1682 | { | |
645fcc9d LZ |
1683 | struct cpuset *cs = cgroup_cs(cgrp); |
1684 | struct cpuset *trialcs; | |
5d21cc2d | 1685 | int retval = -ENODEV; |
e3712395 | 1686 | |
3a5a6d0c TH |
1687 | /* |
1688 | * CPU or memory hotunplug may leave @cs w/o any execution | |
1689 | * resources, in which case the hotplug code asynchronously updates | |
1690 | * configuration and transfers all tasks to the nearest ancestor | |
1691 | * which can execute. | |
1692 | * | |
1693 | * As writes to "cpus" or "mems" may restore @cs's execution | |
1694 | * resources, wait for the previously scheduled operations before | |
1695 | * proceeding, so that we don't end up keep removing tasks added | |
1696 | * after execution capability is restored. | |
1697 | */ | |
1698 | flush_work(&cpuset_hotplug_work); | |
1699 | ||
5d21cc2d TH |
1700 | mutex_lock(&cpuset_mutex); |
1701 | if (!is_cpuset_online(cs)) | |
1702 | goto out_unlock; | |
e3712395 | 1703 | |
645fcc9d | 1704 | trialcs = alloc_trial_cpuset(cs); |
b75f38d6 LZ |
1705 | if (!trialcs) { |
1706 | retval = -ENOMEM; | |
5d21cc2d | 1707 | goto out_unlock; |
b75f38d6 | 1708 | } |
645fcc9d | 1709 | |
e3712395 PM |
1710 | switch (cft->private) { |
1711 | case FILE_CPULIST: | |
645fcc9d | 1712 | retval = update_cpumask(cs, trialcs, buf); |
e3712395 PM |
1713 | break; |
1714 | case FILE_MEMLIST: | |
645fcc9d | 1715 | retval = update_nodemask(cs, trialcs, buf); |
e3712395 PM |
1716 | break; |
1717 | default: | |
1718 | retval = -EINVAL; | |
1719 | break; | |
1720 | } | |
645fcc9d LZ |
1721 | |
1722 | free_trial_cpuset(trialcs); | |
5d21cc2d TH |
1723 | out_unlock: |
1724 | mutex_unlock(&cpuset_mutex); | |
e3712395 PM |
1725 | return retval; |
1726 | } | |
1727 | ||
1da177e4 LT |
1728 | /* |
1729 | * These ascii lists should be read in a single call, by using a user | |
1730 | * buffer large enough to hold the entire map. If read in smaller | |
1731 | * chunks, there is no guarantee of atomicity. Since the display format | |
1732 | * used, list of ranges of sequential numbers, is variable length, | |
1733 | * and since these maps can change value dynamically, one could read | |
1734 | * gibberish by doing partial reads while a list was changing. | |
1735 | * A single large read to a buffer that crosses a page boundary is | |
1736 | * ok, because the result being copied to user land is not recomputed | |
1737 | * across a page fault. | |
1738 | */ | |
1739 | ||
9303e0c4 | 1740 | static size_t cpuset_sprintf_cpulist(char *page, struct cpuset *cs) |
1da177e4 | 1741 | { |
9303e0c4 | 1742 | size_t count; |
1da177e4 | 1743 | |
3d3f26a7 | 1744 | mutex_lock(&callback_mutex); |
9303e0c4 | 1745 | count = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); |
3d3f26a7 | 1746 | mutex_unlock(&callback_mutex); |
1da177e4 | 1747 | |
9303e0c4 | 1748 | return count; |
1da177e4 LT |
1749 | } |
1750 | ||
9303e0c4 | 1751 | static size_t cpuset_sprintf_memlist(char *page, struct cpuset *cs) |
1da177e4 | 1752 | { |
9303e0c4 | 1753 | size_t count; |
1da177e4 | 1754 | |
3d3f26a7 | 1755 | mutex_lock(&callback_mutex); |
9303e0c4 | 1756 | count = nodelist_scnprintf(page, PAGE_SIZE, cs->mems_allowed); |
3d3f26a7 | 1757 | mutex_unlock(&callback_mutex); |
1da177e4 | 1758 | |
9303e0c4 | 1759 | return count; |
1da177e4 LT |
1760 | } |
1761 | ||
c9e5fe66 | 1762 | static ssize_t cpuset_common_file_read(struct cgroup *cgrp, |
8793d854 PM |
1763 | struct cftype *cft, |
1764 | struct file *file, | |
1765 | char __user *buf, | |
1766 | size_t nbytes, loff_t *ppos) | |
1da177e4 | 1767 | { |
c9e5fe66 | 1768 | struct cpuset *cs = cgroup_cs(cgrp); |
1da177e4 LT |
1769 | cpuset_filetype_t type = cft->private; |
1770 | char *page; | |
1771 | ssize_t retval = 0; | |
1772 | char *s; | |
1da177e4 | 1773 | |
e12ba74d | 1774 | if (!(page = (char *)__get_free_page(GFP_TEMPORARY))) |
1da177e4 LT |
1775 | return -ENOMEM; |
1776 | ||
1777 | s = page; | |
1778 | ||
1779 | switch (type) { | |
1780 | case FILE_CPULIST: | |
1781 | s += cpuset_sprintf_cpulist(s, cs); | |
1782 | break; | |
1783 | case FILE_MEMLIST: | |
1784 | s += cpuset_sprintf_memlist(s, cs); | |
1785 | break; | |
1da177e4 LT |
1786 | default: |
1787 | retval = -EINVAL; | |
1788 | goto out; | |
1789 | } | |
1790 | *s++ = '\n'; | |
1da177e4 | 1791 | |
eacaa1f5 | 1792 | retval = simple_read_from_buffer(buf, nbytes, ppos, page, s - page); |
1da177e4 LT |
1793 | out: |
1794 | free_page((unsigned long)page); | |
1795 | return retval; | |
1796 | } | |
1797 | ||
c9e5fe66 | 1798 | static u64 cpuset_read_u64(struct cgroup *cgrp, struct cftype *cft) |
700fe1ab | 1799 | { |
c9e5fe66 | 1800 | struct cpuset *cs = cgroup_cs(cgrp); |
700fe1ab PM |
1801 | cpuset_filetype_t type = cft->private; |
1802 | switch (type) { | |
1803 | case FILE_CPU_EXCLUSIVE: | |
1804 | return is_cpu_exclusive(cs); | |
1805 | case FILE_MEM_EXCLUSIVE: | |
1806 | return is_mem_exclusive(cs); | |
78608366 PM |
1807 | case FILE_MEM_HARDWALL: |
1808 | return is_mem_hardwall(cs); | |
700fe1ab PM |
1809 | case FILE_SCHED_LOAD_BALANCE: |
1810 | return is_sched_load_balance(cs); | |
1811 | case FILE_MEMORY_MIGRATE: | |
1812 | return is_memory_migrate(cs); | |
1813 | case FILE_MEMORY_PRESSURE_ENABLED: | |
1814 | return cpuset_memory_pressure_enabled; | |
1815 | case FILE_MEMORY_PRESSURE: | |
1816 | return fmeter_getrate(&cs->fmeter); | |
1817 | case FILE_SPREAD_PAGE: | |
1818 | return is_spread_page(cs); | |
1819 | case FILE_SPREAD_SLAB: | |
1820 | return is_spread_slab(cs); | |
1821 | default: | |
1822 | BUG(); | |
1823 | } | |
cf417141 MK |
1824 | |
1825 | /* Unreachable but makes gcc happy */ | |
1826 | return 0; | |
700fe1ab | 1827 | } |
1da177e4 | 1828 | |
c9e5fe66 | 1829 | static s64 cpuset_read_s64(struct cgroup *cgrp, struct cftype *cft) |
5be7a479 | 1830 | { |
c9e5fe66 | 1831 | struct cpuset *cs = cgroup_cs(cgrp); |
5be7a479 PM |
1832 | cpuset_filetype_t type = cft->private; |
1833 | switch (type) { | |
1834 | case FILE_SCHED_RELAX_DOMAIN_LEVEL: | |
1835 | return cs->relax_domain_level; | |
1836 | default: | |
1837 | BUG(); | |
1838 | } | |
cf417141 MK |
1839 | |
1840 | /* Unrechable but makes gcc happy */ | |
1841 | return 0; | |
5be7a479 PM |
1842 | } |
1843 | ||
1da177e4 LT |
1844 | |
1845 | /* | |
1846 | * for the common functions, 'private' gives the type of file | |
1847 | */ | |
1848 | ||
addf2c73 PM |
1849 | static struct cftype files[] = { |
1850 | { | |
1851 | .name = "cpus", | |
1852 | .read = cpuset_common_file_read, | |
e3712395 PM |
1853 | .write_string = cpuset_write_resmask, |
1854 | .max_write_len = (100U + 6 * NR_CPUS), | |
addf2c73 PM |
1855 | .private = FILE_CPULIST, |
1856 | }, | |
1857 | ||
1858 | { | |
1859 | .name = "mems", | |
1860 | .read = cpuset_common_file_read, | |
e3712395 PM |
1861 | .write_string = cpuset_write_resmask, |
1862 | .max_write_len = (100U + 6 * MAX_NUMNODES), | |
addf2c73 PM |
1863 | .private = FILE_MEMLIST, |
1864 | }, | |
1865 | ||
1866 | { | |
1867 | .name = "cpu_exclusive", | |
1868 | .read_u64 = cpuset_read_u64, | |
1869 | .write_u64 = cpuset_write_u64, | |
1870 | .private = FILE_CPU_EXCLUSIVE, | |
1871 | }, | |
1872 | ||
1873 | { | |
1874 | .name = "mem_exclusive", | |
1875 | .read_u64 = cpuset_read_u64, | |
1876 | .write_u64 = cpuset_write_u64, | |
1877 | .private = FILE_MEM_EXCLUSIVE, | |
1878 | }, | |
1879 | ||
78608366 PM |
1880 | { |
1881 | .name = "mem_hardwall", | |
1882 | .read_u64 = cpuset_read_u64, | |
1883 | .write_u64 = cpuset_write_u64, | |
1884 | .private = FILE_MEM_HARDWALL, | |
1885 | }, | |
1886 | ||
addf2c73 PM |
1887 | { |
1888 | .name = "sched_load_balance", | |
1889 | .read_u64 = cpuset_read_u64, | |
1890 | .write_u64 = cpuset_write_u64, | |
1891 | .private = FILE_SCHED_LOAD_BALANCE, | |
1892 | }, | |
1893 | ||
1894 | { | |
1895 | .name = "sched_relax_domain_level", | |
5be7a479 PM |
1896 | .read_s64 = cpuset_read_s64, |
1897 | .write_s64 = cpuset_write_s64, | |
addf2c73 PM |
1898 | .private = FILE_SCHED_RELAX_DOMAIN_LEVEL, |
1899 | }, | |
1900 | ||
1901 | { | |
1902 | .name = "memory_migrate", | |
1903 | .read_u64 = cpuset_read_u64, | |
1904 | .write_u64 = cpuset_write_u64, | |
1905 | .private = FILE_MEMORY_MIGRATE, | |
1906 | }, | |
1907 | ||
1908 | { | |
1909 | .name = "memory_pressure", | |
1910 | .read_u64 = cpuset_read_u64, | |
1911 | .write_u64 = cpuset_write_u64, | |
1912 | .private = FILE_MEMORY_PRESSURE, | |
099fca32 | 1913 | .mode = S_IRUGO, |
addf2c73 PM |
1914 | }, |
1915 | ||
1916 | { | |
1917 | .name = "memory_spread_page", | |
1918 | .read_u64 = cpuset_read_u64, | |
1919 | .write_u64 = cpuset_write_u64, | |
1920 | .private = FILE_SPREAD_PAGE, | |
1921 | }, | |
1922 | ||
1923 | { | |
1924 | .name = "memory_spread_slab", | |
1925 | .read_u64 = cpuset_read_u64, | |
1926 | .write_u64 = cpuset_write_u64, | |
1927 | .private = FILE_SPREAD_SLAB, | |
1928 | }, | |
3e0d98b9 | 1929 | |
4baf6e33 TH |
1930 | { |
1931 | .name = "memory_pressure_enabled", | |
1932 | .flags = CFTYPE_ONLY_ON_ROOT, | |
1933 | .read_u64 = cpuset_read_u64, | |
1934 | .write_u64 = cpuset_write_u64, | |
1935 | .private = FILE_MEMORY_PRESSURE_ENABLED, | |
1936 | }, | |
1da177e4 | 1937 | |
4baf6e33 TH |
1938 | { } /* terminate */ |
1939 | }; | |
1da177e4 LT |
1940 | |
1941 | /* | |
92fb9748 | 1942 | * cpuset_css_alloc - allocate a cpuset css |
c9e5fe66 | 1943 | * cgrp: control group that the new cpuset will be part of |
1da177e4 LT |
1944 | */ |
1945 | ||
c9e5fe66 | 1946 | static struct cgroup_subsys_state *cpuset_css_alloc(struct cgroup *cgrp) |
1da177e4 | 1947 | { |
c8f699bb | 1948 | struct cpuset *cs; |
1da177e4 | 1949 | |
c9e5fe66 | 1950 | if (!cgrp->parent) |
8793d854 | 1951 | return &top_cpuset.css; |
033fa1c5 | 1952 | |
c8f699bb | 1953 | cs = kzalloc(sizeof(*cs), GFP_KERNEL); |
1da177e4 | 1954 | if (!cs) |
8793d854 | 1955 | return ERR_PTR(-ENOMEM); |
300ed6cb LZ |
1956 | if (!alloc_cpumask_var(&cs->cpus_allowed, GFP_KERNEL)) { |
1957 | kfree(cs); | |
1958 | return ERR_PTR(-ENOMEM); | |
1959 | } | |
1da177e4 | 1960 | |
029190c5 | 1961 | set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); |
300ed6cb | 1962 | cpumask_clear(cs->cpus_allowed); |
f9a86fcb | 1963 | nodes_clear(cs->mems_allowed); |
3e0d98b9 | 1964 | fmeter_init(&cs->fmeter); |
1d3504fc | 1965 | cs->relax_domain_level = -1; |
1da177e4 | 1966 | |
c8f699bb TH |
1967 | return &cs->css; |
1968 | } | |
1969 | ||
1970 | static int cpuset_css_online(struct cgroup *cgrp) | |
1971 | { | |
1972 | struct cpuset *cs = cgroup_cs(cgrp); | |
c431069f | 1973 | struct cpuset *parent = parent_cs(cs); |
ae8086ce TH |
1974 | struct cpuset *tmp_cs; |
1975 | struct cgroup *pos_cg; | |
c8f699bb TH |
1976 | |
1977 | if (!parent) | |
1978 | return 0; | |
1979 | ||
5d21cc2d TH |
1980 | mutex_lock(&cpuset_mutex); |
1981 | ||
efeb77b2 | 1982 | set_bit(CS_ONLINE, &cs->flags); |
c8f699bb TH |
1983 | if (is_spread_page(parent)) |
1984 | set_bit(CS_SPREAD_PAGE, &cs->flags); | |
1985 | if (is_spread_slab(parent)) | |
1986 | set_bit(CS_SPREAD_SLAB, &cs->flags); | |
1da177e4 | 1987 | |
202f72d5 | 1988 | number_of_cpusets++; |
033fa1c5 | 1989 | |
c8f699bb | 1990 | if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags)) |
5d21cc2d | 1991 | goto out_unlock; |
033fa1c5 TH |
1992 | |
1993 | /* | |
1994 | * Clone @parent's configuration if CGRP_CPUSET_CLONE_CHILDREN is | |
1995 | * set. This flag handling is implemented in cgroup core for | |
1996 | * histrical reasons - the flag may be specified during mount. | |
1997 | * | |
1998 | * Currently, if any sibling cpusets have exclusive cpus or mem, we | |
1999 | * refuse to clone the configuration - thereby refusing the task to | |
2000 | * be entered, and as a result refusing the sys_unshare() or | |
2001 | * clone() which initiated it. If this becomes a problem for some | |
2002 | * users who wish to allow that scenario, then this could be | |
2003 | * changed to grant parent->cpus_allowed-sibling_cpus_exclusive | |
2004 | * (and likewise for mems) to the new cgroup. | |
2005 | */ | |
ae8086ce TH |
2006 | rcu_read_lock(); |
2007 | cpuset_for_each_child(tmp_cs, pos_cg, parent) { | |
2008 | if (is_mem_exclusive(tmp_cs) || is_cpu_exclusive(tmp_cs)) { | |
2009 | rcu_read_unlock(); | |
5d21cc2d | 2010 | goto out_unlock; |
ae8086ce | 2011 | } |
033fa1c5 | 2012 | } |
ae8086ce | 2013 | rcu_read_unlock(); |
033fa1c5 TH |
2014 | |
2015 | mutex_lock(&callback_mutex); | |
2016 | cs->mems_allowed = parent->mems_allowed; | |
2017 | cpumask_copy(cs->cpus_allowed, parent->cpus_allowed); | |
2018 | mutex_unlock(&callback_mutex); | |
5d21cc2d TH |
2019 | out_unlock: |
2020 | mutex_unlock(&cpuset_mutex); | |
c8f699bb TH |
2021 | return 0; |
2022 | } | |
2023 | ||
2024 | static void cpuset_css_offline(struct cgroup *cgrp) | |
2025 | { | |
2026 | struct cpuset *cs = cgroup_cs(cgrp); | |
2027 | ||
5d21cc2d | 2028 | mutex_lock(&cpuset_mutex); |
c8f699bb TH |
2029 | |
2030 | if (is_sched_load_balance(cs)) | |
2031 | update_flag(CS_SCHED_LOAD_BALANCE, cs, 0); | |
2032 | ||
2033 | number_of_cpusets--; | |
efeb77b2 | 2034 | clear_bit(CS_ONLINE, &cs->flags); |
c8f699bb | 2035 | |
5d21cc2d | 2036 | mutex_unlock(&cpuset_mutex); |
1da177e4 LT |
2037 | } |
2038 | ||
029190c5 | 2039 | /* |
029190c5 PJ |
2040 | * If the cpuset being removed has its flag 'sched_load_balance' |
2041 | * enabled, then simulate turning sched_load_balance off, which | |
699140ba | 2042 | * will call rebuild_sched_domains_locked(). |
029190c5 PJ |
2043 | */ |
2044 | ||
c9e5fe66 | 2045 | static void cpuset_css_free(struct cgroup *cgrp) |
1da177e4 | 2046 | { |
c9e5fe66 | 2047 | struct cpuset *cs = cgroup_cs(cgrp); |
1da177e4 | 2048 | |
300ed6cb | 2049 | free_cpumask_var(cs->cpus_allowed); |
8793d854 | 2050 | kfree(cs); |
1da177e4 LT |
2051 | } |
2052 | ||
8793d854 PM |
2053 | struct cgroup_subsys cpuset_subsys = { |
2054 | .name = "cpuset", | |
92fb9748 | 2055 | .css_alloc = cpuset_css_alloc, |
c8f699bb TH |
2056 | .css_online = cpuset_css_online, |
2057 | .css_offline = cpuset_css_offline, | |
92fb9748 | 2058 | .css_free = cpuset_css_free, |
8793d854 | 2059 | .can_attach = cpuset_can_attach, |
452477fa | 2060 | .cancel_attach = cpuset_cancel_attach, |
8793d854 | 2061 | .attach = cpuset_attach, |
8793d854 | 2062 | .subsys_id = cpuset_subsys_id, |
4baf6e33 | 2063 | .base_cftypes = files, |
8793d854 PM |
2064 | .early_init = 1, |
2065 | }; | |
2066 | ||
1da177e4 LT |
2067 | /** |
2068 | * cpuset_init - initialize cpusets at system boot | |
2069 | * | |
2070 | * Description: Initialize top_cpuset and the cpuset internal file system, | |
2071 | **/ | |
2072 | ||
2073 | int __init cpuset_init(void) | |
2074 | { | |
8793d854 | 2075 | int err = 0; |
1da177e4 | 2076 | |
58568d2a MX |
2077 | if (!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL)) |
2078 | BUG(); | |
2079 | ||
300ed6cb | 2080 | cpumask_setall(top_cpuset.cpus_allowed); |
f9a86fcb | 2081 | nodes_setall(top_cpuset.mems_allowed); |
1da177e4 | 2082 | |
3e0d98b9 | 2083 | fmeter_init(&top_cpuset.fmeter); |
029190c5 | 2084 | set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags); |
1d3504fc | 2085 | top_cpuset.relax_domain_level = -1; |
1da177e4 | 2086 | |
1da177e4 LT |
2087 | err = register_filesystem(&cpuset_fs_type); |
2088 | if (err < 0) | |
8793d854 PM |
2089 | return err; |
2090 | ||
2341d1b6 LZ |
2091 | if (!alloc_cpumask_var(&cpus_attach, GFP_KERNEL)) |
2092 | BUG(); | |
2093 | ||
202f72d5 | 2094 | number_of_cpusets = 1; |
8793d854 | 2095 | return 0; |
1da177e4 LT |
2096 | } |
2097 | ||
b1aac8bb | 2098 | /* |
cf417141 | 2099 | * If CPU and/or memory hotplug handlers, below, unplug any CPUs |
b1aac8bb PJ |
2100 | * or memory nodes, we need to walk over the cpuset hierarchy, |
2101 | * removing that CPU or node from all cpusets. If this removes the | |
956db3ca CW |
2102 | * last CPU or node from a cpuset, then move the tasks in the empty |
2103 | * cpuset to its next-highest non-empty parent. | |
b1aac8bb | 2104 | */ |
956db3ca CW |
2105 | static void remove_tasks_in_empty_cpuset(struct cpuset *cs) |
2106 | { | |
2107 | struct cpuset *parent; | |
2108 | ||
956db3ca CW |
2109 | /* |
2110 | * Find its next-highest non-empty parent, (top cpuset | |
2111 | * has online cpus, so can't be empty). | |
2112 | */ | |
c431069f | 2113 | parent = parent_cs(cs); |
300ed6cb | 2114 | while (cpumask_empty(parent->cpus_allowed) || |
b4501295 | 2115 | nodes_empty(parent->mems_allowed)) |
c431069f | 2116 | parent = parent_cs(parent); |
956db3ca | 2117 | |
8cc99345 TH |
2118 | if (cgroup_transfer_tasks(parent->css.cgroup, cs->css.cgroup)) { |
2119 | rcu_read_lock(); | |
2120 | printk(KERN_ERR "cpuset: failed to transfer tasks out of empty cpuset %s\n", | |
2121 | cgroup_name(cs->css.cgroup)); | |
2122 | rcu_read_unlock(); | |
2123 | } | |
956db3ca CW |
2124 | } |
2125 | ||
deb7aa30 | 2126 | /** |
388afd85 | 2127 | * cpuset_hotplug_update_tasks - update tasks in a cpuset for hotunplug |
deb7aa30 | 2128 | * @cs: cpuset in interest |
956db3ca | 2129 | * |
deb7aa30 TH |
2130 | * Compare @cs's cpu and mem masks against top_cpuset and if some have gone |
2131 | * offline, update @cs accordingly. If @cs ends up with no CPU or memory, | |
2132 | * all its tasks are moved to the nearest ancestor with both resources. | |
80d1fa64 | 2133 | */ |
388afd85 | 2134 | static void cpuset_hotplug_update_tasks(struct cpuset *cs) |
80d1fa64 | 2135 | { |
deb7aa30 | 2136 | static cpumask_t off_cpus; |
33ad801d | 2137 | static nodemask_t off_mems; |
5d21cc2d | 2138 | bool is_empty; |
5c5cc623 | 2139 | bool sane = cgroup_sane_behavior(cs->css.cgroup); |
80d1fa64 | 2140 | |
e44193d3 LZ |
2141 | retry: |
2142 | wait_event(cpuset_attach_wq, cs->attach_in_progress == 0); | |
80d1fa64 | 2143 | |
5d21cc2d | 2144 | mutex_lock(&cpuset_mutex); |
7ddf96b0 | 2145 | |
e44193d3 LZ |
2146 | /* |
2147 | * We have raced with task attaching. We wait until attaching | |
2148 | * is finished, so we won't attach a task to an empty cpuset. | |
2149 | */ | |
2150 | if (cs->attach_in_progress) { | |
2151 | mutex_unlock(&cpuset_mutex); | |
2152 | goto retry; | |
2153 | } | |
2154 | ||
deb7aa30 TH |
2155 | cpumask_andnot(&off_cpus, cs->cpus_allowed, top_cpuset.cpus_allowed); |
2156 | nodes_andnot(off_mems, cs->mems_allowed, top_cpuset.mems_allowed); | |
80d1fa64 | 2157 | |
5c5cc623 LZ |
2158 | mutex_lock(&callback_mutex); |
2159 | cpumask_andnot(cs->cpus_allowed, cs->cpus_allowed, &off_cpus); | |
2160 | mutex_unlock(&callback_mutex); | |
2161 | ||
2162 | /* | |
2163 | * If sane_behavior flag is set, we need to update tasks' cpumask | |
f047cecf LZ |
2164 | * for empty cpuset to take on ancestor's cpumask. Otherwise, don't |
2165 | * call update_tasks_cpumask() if the cpuset becomes empty, as | |
2166 | * the tasks in it will be migrated to an ancestor. | |
5c5cc623 LZ |
2167 | */ |
2168 | if ((sane && cpumask_empty(cs->cpus_allowed)) || | |
f047cecf | 2169 | (!cpumask_empty(&off_cpus) && !cpumask_empty(cs->cpus_allowed))) |
deb7aa30 | 2170 | update_tasks_cpumask(cs, NULL); |
80d1fa64 | 2171 | |
5c5cc623 LZ |
2172 | mutex_lock(&callback_mutex); |
2173 | nodes_andnot(cs->mems_allowed, cs->mems_allowed, off_mems); | |
2174 | mutex_unlock(&callback_mutex); | |
2175 | ||
2176 | /* | |
2177 | * If sane_behavior flag is set, we need to update tasks' nodemask | |
f047cecf LZ |
2178 | * for empty cpuset to take on ancestor's nodemask. Otherwise, don't |
2179 | * call update_tasks_nodemask() if the cpuset becomes empty, as | |
2180 | * the tasks in it will be migratd to an ancestor. | |
5c5cc623 LZ |
2181 | */ |
2182 | if ((sane && nodes_empty(cs->mems_allowed)) || | |
f047cecf | 2183 | (!nodes_empty(off_mems) && !nodes_empty(cs->mems_allowed))) |
33ad801d | 2184 | update_tasks_nodemask(cs, NULL); |
deb7aa30 | 2185 | |
5d21cc2d TH |
2186 | is_empty = cpumask_empty(cs->cpus_allowed) || |
2187 | nodes_empty(cs->mems_allowed); | |
8d033948 | 2188 | |
5d21cc2d TH |
2189 | mutex_unlock(&cpuset_mutex); |
2190 | ||
2191 | /* | |
5c5cc623 LZ |
2192 | * If sane_behavior flag is set, we'll keep tasks in empty cpusets. |
2193 | * | |
2194 | * Otherwise move tasks to the nearest ancestor with execution | |
2195 | * resources. This is full cgroup operation which will | |
5d21cc2d TH |
2196 | * also call back into cpuset. Should be done outside any lock. |
2197 | */ | |
5c5cc623 | 2198 | if (!sane && is_empty) |
5d21cc2d | 2199 | remove_tasks_in_empty_cpuset(cs); |
b1aac8bb PJ |
2200 | } |
2201 | ||
deb7aa30 | 2202 | /** |
3a5a6d0c | 2203 | * cpuset_hotplug_workfn - handle CPU/memory hotunplug for a cpuset |
956db3ca | 2204 | * |
deb7aa30 TH |
2205 | * This function is called after either CPU or memory configuration has |
2206 | * changed and updates cpuset accordingly. The top_cpuset is always | |
2207 | * synchronized to cpu_active_mask and N_MEMORY, which is necessary in | |
2208 | * order to make cpusets transparent (of no affect) on systems that are | |
2209 | * actively using CPU hotplug but making no active use of cpusets. | |
956db3ca | 2210 | * |
deb7aa30 | 2211 | * Non-root cpusets are only affected by offlining. If any CPUs or memory |
388afd85 LZ |
2212 | * nodes have been taken down, cpuset_hotplug_update_tasks() is invoked on |
2213 | * all descendants. | |
956db3ca | 2214 | * |
deb7aa30 TH |
2215 | * Note that CPU offlining during suspend is ignored. We don't modify |
2216 | * cpusets across suspend/resume cycles at all. | |
956db3ca | 2217 | */ |
3a5a6d0c | 2218 | static void cpuset_hotplug_workfn(struct work_struct *work) |
b1aac8bb | 2219 | { |
5c5cc623 LZ |
2220 | static cpumask_t new_cpus; |
2221 | static nodemask_t new_mems; | |
deb7aa30 | 2222 | bool cpus_updated, mems_updated; |
b1aac8bb | 2223 | |
5d21cc2d | 2224 | mutex_lock(&cpuset_mutex); |
956db3ca | 2225 | |
deb7aa30 TH |
2226 | /* fetch the available cpus/mems and find out which changed how */ |
2227 | cpumask_copy(&new_cpus, cpu_active_mask); | |
2228 | new_mems = node_states[N_MEMORY]; | |
7ddf96b0 | 2229 | |
deb7aa30 | 2230 | cpus_updated = !cpumask_equal(top_cpuset.cpus_allowed, &new_cpus); |
deb7aa30 | 2231 | mems_updated = !nodes_equal(top_cpuset.mems_allowed, new_mems); |
7ddf96b0 | 2232 | |
deb7aa30 TH |
2233 | /* synchronize cpus_allowed to cpu_active_mask */ |
2234 | if (cpus_updated) { | |
2235 | mutex_lock(&callback_mutex); | |
2236 | cpumask_copy(top_cpuset.cpus_allowed, &new_cpus); | |
2237 | mutex_unlock(&callback_mutex); | |
2238 | /* we don't mess with cpumasks of tasks in top_cpuset */ | |
2239 | } | |
b4501295 | 2240 | |
deb7aa30 TH |
2241 | /* synchronize mems_allowed to N_MEMORY */ |
2242 | if (mems_updated) { | |
deb7aa30 TH |
2243 | mutex_lock(&callback_mutex); |
2244 | top_cpuset.mems_allowed = new_mems; | |
2245 | mutex_unlock(&callback_mutex); | |
33ad801d | 2246 | update_tasks_nodemask(&top_cpuset, NULL); |
deb7aa30 | 2247 | } |
b4501295 | 2248 | |
388afd85 LZ |
2249 | mutex_unlock(&cpuset_mutex); |
2250 | ||
5c5cc623 LZ |
2251 | /* if cpus or mems changed, we need to propagate to descendants */ |
2252 | if (cpus_updated || mems_updated) { | |
deb7aa30 | 2253 | struct cpuset *cs; |
fc560a26 | 2254 | struct cgroup *pos_cgrp; |
f9b4fb8d | 2255 | |
fc560a26 | 2256 | rcu_read_lock(); |
388afd85 LZ |
2257 | cpuset_for_each_descendant_pre(cs, pos_cgrp, &top_cpuset) { |
2258 | if (!css_tryget(&cs->css)) | |
2259 | continue; | |
2260 | rcu_read_unlock(); | |
7ddf96b0 | 2261 | |
388afd85 | 2262 | cpuset_hotplug_update_tasks(cs); |
b4501295 | 2263 | |
388afd85 LZ |
2264 | rcu_read_lock(); |
2265 | css_put(&cs->css); | |
2266 | } | |
2267 | rcu_read_unlock(); | |
2268 | } | |
8d033948 | 2269 | |
deb7aa30 | 2270 | /* rebuild sched domains if cpus_allowed has changed */ |
e0e80a02 LZ |
2271 | if (cpus_updated) |
2272 | rebuild_sched_domains(); | |
b1aac8bb PJ |
2273 | } |
2274 | ||
7ddf96b0 | 2275 | void cpuset_update_active_cpus(bool cpu_online) |
4c4d50f7 | 2276 | { |
3a5a6d0c TH |
2277 | /* |
2278 | * We're inside cpu hotplug critical region which usually nests | |
2279 | * inside cgroup synchronization. Bounce actual hotplug processing | |
2280 | * to a work item to avoid reverse locking order. | |
2281 | * | |
2282 | * We still need to do partition_sched_domains() synchronously; | |
2283 | * otherwise, the scheduler will get confused and put tasks to the | |
2284 | * dead CPU. Fall back to the default single domain. | |
2285 | * cpuset_hotplug_workfn() will rebuild it as necessary. | |
2286 | */ | |
2287 | partition_sched_domains(1, NULL, NULL); | |
2288 | schedule_work(&cpuset_hotplug_work); | |
4c4d50f7 | 2289 | } |
4c4d50f7 | 2290 | |
38837fc7 | 2291 | /* |
38d7bee9 LJ |
2292 | * Keep top_cpuset.mems_allowed tracking node_states[N_MEMORY]. |
2293 | * Call this routine anytime after node_states[N_MEMORY] changes. | |
a1cd2b13 | 2294 | * See cpuset_update_active_cpus() for CPU hotplug handling. |
38837fc7 | 2295 | */ |
f481891f MX |
2296 | static int cpuset_track_online_nodes(struct notifier_block *self, |
2297 | unsigned long action, void *arg) | |
38837fc7 | 2298 | { |
3a5a6d0c | 2299 | schedule_work(&cpuset_hotplug_work); |
f481891f | 2300 | return NOTIFY_OK; |
38837fc7 | 2301 | } |
d8f10cb3 AM |
2302 | |
2303 | static struct notifier_block cpuset_track_online_nodes_nb = { | |
2304 | .notifier_call = cpuset_track_online_nodes, | |
2305 | .priority = 10, /* ??! */ | |
2306 | }; | |
38837fc7 | 2307 | |
1da177e4 LT |
2308 | /** |
2309 | * cpuset_init_smp - initialize cpus_allowed | |
2310 | * | |
2311 | * Description: Finish top cpuset after cpu, node maps are initialized | |
d8f10cb3 | 2312 | */ |
1da177e4 LT |
2313 | void __init cpuset_init_smp(void) |
2314 | { | |
6ad4c188 | 2315 | cpumask_copy(top_cpuset.cpus_allowed, cpu_active_mask); |
38d7bee9 | 2316 | top_cpuset.mems_allowed = node_states[N_MEMORY]; |
33ad801d | 2317 | top_cpuset.old_mems_allowed = top_cpuset.mems_allowed; |
4c4d50f7 | 2318 | |
d8f10cb3 | 2319 | register_hotmemory_notifier(&cpuset_track_online_nodes_nb); |
1da177e4 LT |
2320 | } |
2321 | ||
2322 | /** | |
1da177e4 LT |
2323 | * cpuset_cpus_allowed - return cpus_allowed mask from a tasks cpuset. |
2324 | * @tsk: pointer to task_struct from which to obtain cpuset->cpus_allowed. | |
6af866af | 2325 | * @pmask: pointer to struct cpumask variable to receive cpus_allowed set. |
1da177e4 | 2326 | * |
300ed6cb | 2327 | * Description: Returns the cpumask_var_t cpus_allowed of the cpuset |
1da177e4 | 2328 | * attached to the specified @tsk. Guaranteed to return some non-empty |
5f054e31 | 2329 | * subset of cpu_online_mask, even if this means going outside the |
1da177e4 LT |
2330 | * tasks cpuset. |
2331 | **/ | |
2332 | ||
6af866af | 2333 | void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) |
1da177e4 | 2334 | { |
070b57fc LZ |
2335 | struct cpuset *cpus_cs; |
2336 | ||
3d3f26a7 | 2337 | mutex_lock(&callback_mutex); |
909d75a3 | 2338 | task_lock(tsk); |
070b57fc LZ |
2339 | cpus_cs = effective_cpumask_cpuset(task_cs(tsk)); |
2340 | guarantee_online_cpus(cpus_cs, pmask); | |
909d75a3 | 2341 | task_unlock(tsk); |
897f0b3c | 2342 | mutex_unlock(&callback_mutex); |
1da177e4 LT |
2343 | } |
2344 | ||
2baab4e9 | 2345 | void cpuset_cpus_allowed_fallback(struct task_struct *tsk) |
9084bb82 | 2346 | { |
070b57fc | 2347 | const struct cpuset *cpus_cs; |
9084bb82 ON |
2348 | |
2349 | rcu_read_lock(); | |
070b57fc LZ |
2350 | cpus_cs = effective_cpumask_cpuset(task_cs(tsk)); |
2351 | do_set_cpus_allowed(tsk, cpus_cs->cpus_allowed); | |
9084bb82 ON |
2352 | rcu_read_unlock(); |
2353 | ||
2354 | /* | |
2355 | * We own tsk->cpus_allowed, nobody can change it under us. | |
2356 | * | |
2357 | * But we used cs && cs->cpus_allowed lockless and thus can | |
2358 | * race with cgroup_attach_task() or update_cpumask() and get | |
2359 | * the wrong tsk->cpus_allowed. However, both cases imply the | |
2360 | * subsequent cpuset_change_cpumask()->set_cpus_allowed_ptr() | |
2361 | * which takes task_rq_lock(). | |
2362 | * | |
2363 | * If we are called after it dropped the lock we must see all | |
2364 | * changes in tsk_cs()->cpus_allowed. Otherwise we can temporary | |
2365 | * set any mask even if it is not right from task_cs() pov, | |
2366 | * the pending set_cpus_allowed_ptr() will fix things. | |
2baab4e9 PZ |
2367 | * |
2368 | * select_fallback_rq() will fix things ups and set cpu_possible_mask | |
2369 | * if required. | |
9084bb82 | 2370 | */ |
9084bb82 ON |
2371 | } |
2372 | ||
1da177e4 LT |
2373 | void cpuset_init_current_mems_allowed(void) |
2374 | { | |
f9a86fcb | 2375 | nodes_setall(current->mems_allowed); |
1da177e4 LT |
2376 | } |
2377 | ||
909d75a3 PJ |
2378 | /** |
2379 | * cpuset_mems_allowed - return mems_allowed mask from a tasks cpuset. | |
2380 | * @tsk: pointer to task_struct from which to obtain cpuset->mems_allowed. | |
2381 | * | |
2382 | * Description: Returns the nodemask_t mems_allowed of the cpuset | |
2383 | * attached to the specified @tsk. Guaranteed to return some non-empty | |
38d7bee9 | 2384 | * subset of node_states[N_MEMORY], even if this means going outside the |
909d75a3 PJ |
2385 | * tasks cpuset. |
2386 | **/ | |
2387 | ||
2388 | nodemask_t cpuset_mems_allowed(struct task_struct *tsk) | |
2389 | { | |
070b57fc | 2390 | struct cpuset *mems_cs; |
909d75a3 PJ |
2391 | nodemask_t mask; |
2392 | ||
3d3f26a7 | 2393 | mutex_lock(&callback_mutex); |
909d75a3 | 2394 | task_lock(tsk); |
070b57fc LZ |
2395 | mems_cs = effective_nodemask_cpuset(task_cs(tsk)); |
2396 | guarantee_online_mems(mems_cs, &mask); | |
909d75a3 | 2397 | task_unlock(tsk); |
3d3f26a7 | 2398 | mutex_unlock(&callback_mutex); |
909d75a3 PJ |
2399 | |
2400 | return mask; | |
2401 | } | |
2402 | ||
d9fd8a6d | 2403 | /** |
19770b32 MG |
2404 | * cpuset_nodemask_valid_mems_allowed - check nodemask vs. curremt mems_allowed |
2405 | * @nodemask: the nodemask to be checked | |
d9fd8a6d | 2406 | * |
19770b32 | 2407 | * Are any of the nodes in the nodemask allowed in current->mems_allowed? |
1da177e4 | 2408 | */ |
19770b32 | 2409 | int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask) |
1da177e4 | 2410 | { |
19770b32 | 2411 | return nodes_intersects(*nodemask, current->mems_allowed); |
1da177e4 LT |
2412 | } |
2413 | ||
9bf2229f | 2414 | /* |
78608366 PM |
2415 | * nearest_hardwall_ancestor() - Returns the nearest mem_exclusive or |
2416 | * mem_hardwall ancestor to the specified cpuset. Call holding | |
2417 | * callback_mutex. If no ancestor is mem_exclusive or mem_hardwall | |
2418 | * (an unusual configuration), then returns the root cpuset. | |
9bf2229f | 2419 | */ |
78608366 | 2420 | static const struct cpuset *nearest_hardwall_ancestor(const struct cpuset *cs) |
9bf2229f | 2421 | { |
c431069f TH |
2422 | while (!(is_mem_exclusive(cs) || is_mem_hardwall(cs)) && parent_cs(cs)) |
2423 | cs = parent_cs(cs); | |
9bf2229f PJ |
2424 | return cs; |
2425 | } | |
2426 | ||
d9fd8a6d | 2427 | /** |
a1bc5a4e DR |
2428 | * cpuset_node_allowed_softwall - Can we allocate on a memory node? |
2429 | * @node: is this an allowed node? | |
02a0e53d | 2430 | * @gfp_mask: memory allocation flags |
d9fd8a6d | 2431 | * |
a1bc5a4e DR |
2432 | * If we're in interrupt, yes, we can always allocate. If __GFP_THISNODE is |
2433 | * set, yes, we can always allocate. If node is in our task's mems_allowed, | |
2434 | * yes. If it's not a __GFP_HARDWALL request and this node is in the nearest | |
2435 | * hardwalled cpuset ancestor to this task's cpuset, yes. If the task has been | |
2436 | * OOM killed and has access to memory reserves as specified by the TIF_MEMDIE | |
2437 | * flag, yes. | |
9bf2229f PJ |
2438 | * Otherwise, no. |
2439 | * | |
a1bc5a4e DR |
2440 | * If __GFP_HARDWALL is set, cpuset_node_allowed_softwall() reduces to |
2441 | * cpuset_node_allowed_hardwall(). Otherwise, cpuset_node_allowed_softwall() | |
2442 | * might sleep, and might allow a node from an enclosing cpuset. | |
02a0e53d | 2443 | * |
a1bc5a4e DR |
2444 | * cpuset_node_allowed_hardwall() only handles the simpler case of hardwall |
2445 | * cpusets, and never sleeps. | |
02a0e53d PJ |
2446 | * |
2447 | * The __GFP_THISNODE placement logic is really handled elsewhere, | |
2448 | * by forcibly using a zonelist starting at a specified node, and by | |
2449 | * (in get_page_from_freelist()) refusing to consider the zones for | |
2450 | * any node on the zonelist except the first. By the time any such | |
2451 | * calls get to this routine, we should just shut up and say 'yes'. | |
2452 | * | |
9bf2229f | 2453 | * GFP_USER allocations are marked with the __GFP_HARDWALL bit, |
c596d9f3 DR |
2454 | * and do not allow allocations outside the current tasks cpuset |
2455 | * unless the task has been OOM killed as is marked TIF_MEMDIE. | |
9bf2229f | 2456 | * GFP_KERNEL allocations are not so marked, so can escape to the |
78608366 | 2457 | * nearest enclosing hardwalled ancestor cpuset. |
9bf2229f | 2458 | * |
02a0e53d PJ |
2459 | * Scanning up parent cpusets requires callback_mutex. The |
2460 | * __alloc_pages() routine only calls here with __GFP_HARDWALL bit | |
2461 | * _not_ set if it's a GFP_KERNEL allocation, and all nodes in the | |
2462 | * current tasks mems_allowed came up empty on the first pass over | |
2463 | * the zonelist. So only GFP_KERNEL allocations, if all nodes in the | |
2464 | * cpuset are short of memory, might require taking the callback_mutex | |
2465 | * mutex. | |
9bf2229f | 2466 | * |
36be57ff | 2467 | * The first call here from mm/page_alloc:get_page_from_freelist() |
02a0e53d PJ |
2468 | * has __GFP_HARDWALL set in gfp_mask, enforcing hardwall cpusets, |
2469 | * so no allocation on a node outside the cpuset is allowed (unless | |
2470 | * in interrupt, of course). | |
36be57ff PJ |
2471 | * |
2472 | * The second pass through get_page_from_freelist() doesn't even call | |
2473 | * here for GFP_ATOMIC calls. For those calls, the __alloc_pages() | |
2474 | * variable 'wait' is not set, and the bit ALLOC_CPUSET is not set | |
2475 | * in alloc_flags. That logic and the checks below have the combined | |
2476 | * affect that: | |
9bf2229f PJ |
2477 | * in_interrupt - any node ok (current task context irrelevant) |
2478 | * GFP_ATOMIC - any node ok | |
c596d9f3 | 2479 | * TIF_MEMDIE - any node ok |
78608366 | 2480 | * GFP_KERNEL - any node in enclosing hardwalled cpuset ok |
9bf2229f | 2481 | * GFP_USER - only nodes in current tasks mems allowed ok. |
36be57ff PJ |
2482 | * |
2483 | * Rule: | |
a1bc5a4e | 2484 | * Don't call cpuset_node_allowed_softwall if you can't sleep, unless you |
36be57ff PJ |
2485 | * pass in the __GFP_HARDWALL flag set in gfp_flag, which disables |
2486 | * the code that might scan up ancestor cpusets and sleep. | |
02a0e53d | 2487 | */ |
a1bc5a4e | 2488 | int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask) |
1da177e4 | 2489 | { |
9bf2229f | 2490 | const struct cpuset *cs; /* current cpuset ancestors */ |
29afd49b | 2491 | int allowed; /* is allocation in zone z allowed? */ |
9bf2229f | 2492 | |
9b819d20 | 2493 | if (in_interrupt() || (gfp_mask & __GFP_THISNODE)) |
9bf2229f | 2494 | return 1; |
92d1dbd2 | 2495 | might_sleep_if(!(gfp_mask & __GFP_HARDWALL)); |
9bf2229f PJ |
2496 | if (node_isset(node, current->mems_allowed)) |
2497 | return 1; | |
c596d9f3 DR |
2498 | /* |
2499 | * Allow tasks that have access to memory reserves because they have | |
2500 | * been OOM killed to get memory anywhere. | |
2501 | */ | |
2502 | if (unlikely(test_thread_flag(TIF_MEMDIE))) | |
2503 | return 1; | |
9bf2229f PJ |
2504 | if (gfp_mask & __GFP_HARDWALL) /* If hardwall request, stop here */ |
2505 | return 0; | |
2506 | ||
5563e770 BP |
2507 | if (current->flags & PF_EXITING) /* Let dying task have memory */ |
2508 | return 1; | |
2509 | ||
9bf2229f | 2510 | /* Not hardwall and node outside mems_allowed: scan up cpusets */ |
3d3f26a7 | 2511 | mutex_lock(&callback_mutex); |
053199ed | 2512 | |
053199ed | 2513 | task_lock(current); |
78608366 | 2514 | cs = nearest_hardwall_ancestor(task_cs(current)); |
053199ed PJ |
2515 | task_unlock(current); |
2516 | ||
9bf2229f | 2517 | allowed = node_isset(node, cs->mems_allowed); |
3d3f26a7 | 2518 | mutex_unlock(&callback_mutex); |
9bf2229f | 2519 | return allowed; |
1da177e4 LT |
2520 | } |
2521 | ||
02a0e53d | 2522 | /* |
a1bc5a4e DR |
2523 | * cpuset_node_allowed_hardwall - Can we allocate on a memory node? |
2524 | * @node: is this an allowed node? | |
02a0e53d PJ |
2525 | * @gfp_mask: memory allocation flags |
2526 | * | |
a1bc5a4e DR |
2527 | * If we're in interrupt, yes, we can always allocate. If __GFP_THISNODE is |
2528 | * set, yes, we can always allocate. If node is in our task's mems_allowed, | |
2529 | * yes. If the task has been OOM killed and has access to memory reserves as | |
2530 | * specified by the TIF_MEMDIE flag, yes. | |
2531 | * Otherwise, no. | |
02a0e53d PJ |
2532 | * |
2533 | * The __GFP_THISNODE placement logic is really handled elsewhere, | |
2534 | * by forcibly using a zonelist starting at a specified node, and by | |
2535 | * (in get_page_from_freelist()) refusing to consider the zones for | |
2536 | * any node on the zonelist except the first. By the time any such | |
2537 | * calls get to this routine, we should just shut up and say 'yes'. | |
2538 | * | |
a1bc5a4e DR |
2539 | * Unlike the cpuset_node_allowed_softwall() variant, above, |
2540 | * this variant requires that the node be in the current task's | |
02a0e53d PJ |
2541 | * mems_allowed or that we're in interrupt. It does not scan up the |
2542 | * cpuset hierarchy for the nearest enclosing mem_exclusive cpuset. | |
2543 | * It never sleeps. | |
2544 | */ | |
a1bc5a4e | 2545 | int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask) |
02a0e53d | 2546 | { |
02a0e53d PJ |
2547 | if (in_interrupt() || (gfp_mask & __GFP_THISNODE)) |
2548 | return 1; | |
02a0e53d PJ |
2549 | if (node_isset(node, current->mems_allowed)) |
2550 | return 1; | |
dedf8b79 DW |
2551 | /* |
2552 | * Allow tasks that have access to memory reserves because they have | |
2553 | * been OOM killed to get memory anywhere. | |
2554 | */ | |
2555 | if (unlikely(test_thread_flag(TIF_MEMDIE))) | |
2556 | return 1; | |
02a0e53d PJ |
2557 | return 0; |
2558 | } | |
2559 | ||
825a46af | 2560 | /** |
6adef3eb JS |
2561 | * cpuset_mem_spread_node() - On which node to begin search for a file page |
2562 | * cpuset_slab_spread_node() - On which node to begin search for a slab page | |
825a46af PJ |
2563 | * |
2564 | * If a task is marked PF_SPREAD_PAGE or PF_SPREAD_SLAB (as for | |
2565 | * tasks in a cpuset with is_spread_page or is_spread_slab set), | |
2566 | * and if the memory allocation used cpuset_mem_spread_node() | |
2567 | * to determine on which node to start looking, as it will for | |
2568 | * certain page cache or slab cache pages such as used for file | |
2569 | * system buffers and inode caches, then instead of starting on the | |
2570 | * local node to look for a free page, rather spread the starting | |
2571 | * node around the tasks mems_allowed nodes. | |
2572 | * | |
2573 | * We don't have to worry about the returned node being offline | |
2574 | * because "it can't happen", and even if it did, it would be ok. | |
2575 | * | |
2576 | * The routines calling guarantee_online_mems() are careful to | |
2577 | * only set nodes in task->mems_allowed that are online. So it | |
2578 | * should not be possible for the following code to return an | |
2579 | * offline node. But if it did, that would be ok, as this routine | |
2580 | * is not returning the node where the allocation must be, only | |
2581 | * the node where the search should start. The zonelist passed to | |
2582 | * __alloc_pages() will include all nodes. If the slab allocator | |
2583 | * is passed an offline node, it will fall back to the local node. | |
2584 | * See kmem_cache_alloc_node(). | |
2585 | */ | |
2586 | ||
6adef3eb | 2587 | static int cpuset_spread_node(int *rotor) |
825a46af PJ |
2588 | { |
2589 | int node; | |
2590 | ||
6adef3eb | 2591 | node = next_node(*rotor, current->mems_allowed); |
825a46af PJ |
2592 | if (node == MAX_NUMNODES) |
2593 | node = first_node(current->mems_allowed); | |
6adef3eb | 2594 | *rotor = node; |
825a46af PJ |
2595 | return node; |
2596 | } | |
6adef3eb JS |
2597 | |
2598 | int cpuset_mem_spread_node(void) | |
2599 | { | |
778d3b0f MH |
2600 | if (current->cpuset_mem_spread_rotor == NUMA_NO_NODE) |
2601 | current->cpuset_mem_spread_rotor = | |
2602 | node_random(¤t->mems_allowed); | |
2603 | ||
6adef3eb JS |
2604 | return cpuset_spread_node(¤t->cpuset_mem_spread_rotor); |
2605 | } | |
2606 | ||
2607 | int cpuset_slab_spread_node(void) | |
2608 | { | |
778d3b0f MH |
2609 | if (current->cpuset_slab_spread_rotor == NUMA_NO_NODE) |
2610 | current->cpuset_slab_spread_rotor = | |
2611 | node_random(¤t->mems_allowed); | |
2612 | ||
6adef3eb JS |
2613 | return cpuset_spread_node(¤t->cpuset_slab_spread_rotor); |
2614 | } | |
2615 | ||
825a46af PJ |
2616 | EXPORT_SYMBOL_GPL(cpuset_mem_spread_node); |
2617 | ||
ef08e3b4 | 2618 | /** |
bbe373f2 DR |
2619 | * cpuset_mems_allowed_intersects - Does @tsk1's mems_allowed intersect @tsk2's? |
2620 | * @tsk1: pointer to task_struct of some task. | |
2621 | * @tsk2: pointer to task_struct of some other task. | |
2622 | * | |
2623 | * Description: Return true if @tsk1's mems_allowed intersects the | |
2624 | * mems_allowed of @tsk2. Used by the OOM killer to determine if | |
2625 | * one of the task's memory usage might impact the memory available | |
2626 | * to the other. | |
ef08e3b4 PJ |
2627 | **/ |
2628 | ||
bbe373f2 DR |
2629 | int cpuset_mems_allowed_intersects(const struct task_struct *tsk1, |
2630 | const struct task_struct *tsk2) | |
ef08e3b4 | 2631 | { |
bbe373f2 | 2632 | return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed); |
ef08e3b4 PJ |
2633 | } |
2634 | ||
f440d98f LZ |
2635 | #define CPUSET_NODELIST_LEN (256) |
2636 | ||
75aa1994 DR |
2637 | /** |
2638 | * cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed | |
2639 | * @task: pointer to task_struct of some task. | |
2640 | * | |
2641 | * Description: Prints @task's name, cpuset name, and cached copy of its | |
2642 | * mems_allowed to the kernel log. Must hold task_lock(task) to allow | |
2643 | * dereferencing task_cs(task). | |
2644 | */ | |
2645 | void cpuset_print_task_mems_allowed(struct task_struct *tsk) | |
2646 | { | |
f440d98f LZ |
2647 | /* Statically allocated to prevent using excess stack. */ |
2648 | static char cpuset_nodelist[CPUSET_NODELIST_LEN]; | |
2649 | static DEFINE_SPINLOCK(cpuset_buffer_lock); | |
75aa1994 | 2650 | |
f440d98f | 2651 | struct cgroup *cgrp = task_cs(tsk)->css.cgroup; |
63f43f55 | 2652 | |
cfb5966b | 2653 | rcu_read_lock(); |
f440d98f | 2654 | spin_lock(&cpuset_buffer_lock); |
63f43f55 | 2655 | |
75aa1994 DR |
2656 | nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN, |
2657 | tsk->mems_allowed); | |
2658 | printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n", | |
f440d98f LZ |
2659 | tsk->comm, cgroup_name(cgrp), cpuset_nodelist); |
2660 | ||
75aa1994 | 2661 | spin_unlock(&cpuset_buffer_lock); |
cfb5966b | 2662 | rcu_read_unlock(); |
75aa1994 DR |
2663 | } |
2664 | ||
3e0d98b9 PJ |
2665 | /* |
2666 | * Collection of memory_pressure is suppressed unless | |
2667 | * this flag is enabled by writing "1" to the special | |
2668 | * cpuset file 'memory_pressure_enabled' in the root cpuset. | |
2669 | */ | |
2670 | ||
c5b2aff8 | 2671 | int cpuset_memory_pressure_enabled __read_mostly; |
3e0d98b9 PJ |
2672 | |
2673 | /** | |
2674 | * cpuset_memory_pressure_bump - keep stats of per-cpuset reclaims. | |
2675 | * | |
2676 | * Keep a running average of the rate of synchronous (direct) | |
2677 | * page reclaim efforts initiated by tasks in each cpuset. | |
2678 | * | |
2679 | * This represents the rate at which some task in the cpuset | |
2680 | * ran low on memory on all nodes it was allowed to use, and | |
2681 | * had to enter the kernels page reclaim code in an effort to | |
2682 | * create more free memory by tossing clean pages or swapping | |
2683 | * or writing dirty pages. | |
2684 | * | |
2685 | * Display to user space in the per-cpuset read-only file | |
2686 | * "memory_pressure". Value displayed is an integer | |
2687 | * representing the recent rate of entry into the synchronous | |
2688 | * (direct) page reclaim by any task attached to the cpuset. | |
2689 | **/ | |
2690 | ||
2691 | void __cpuset_memory_pressure_bump(void) | |
2692 | { | |
3e0d98b9 | 2693 | task_lock(current); |
8793d854 | 2694 | fmeter_markevent(&task_cs(current)->fmeter); |
3e0d98b9 PJ |
2695 | task_unlock(current); |
2696 | } | |
2697 | ||
8793d854 | 2698 | #ifdef CONFIG_PROC_PID_CPUSET |
1da177e4 LT |
2699 | /* |
2700 | * proc_cpuset_show() | |
2701 | * - Print tasks cpuset path into seq_file. | |
2702 | * - Used for /proc/<pid>/cpuset. | |
053199ed PJ |
2703 | * - No need to task_lock(tsk) on this tsk->cpuset reference, as it |
2704 | * doesn't really matter if tsk->cpuset changes after we read it, | |
5d21cc2d | 2705 | * and we take cpuset_mutex, keeping cpuset_attach() from changing it |
2df167a3 | 2706 | * anyway. |
1da177e4 | 2707 | */ |
8d8b97ba | 2708 | int proc_cpuset_show(struct seq_file *m, void *unused_v) |
1da177e4 | 2709 | { |
13b41b09 | 2710 | struct pid *pid; |
1da177e4 LT |
2711 | struct task_struct *tsk; |
2712 | char *buf; | |
8793d854 | 2713 | struct cgroup_subsys_state *css; |
99f89551 | 2714 | int retval; |
1da177e4 | 2715 | |
99f89551 | 2716 | retval = -ENOMEM; |
1da177e4 LT |
2717 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
2718 | if (!buf) | |
99f89551 EB |
2719 | goto out; |
2720 | ||
2721 | retval = -ESRCH; | |
13b41b09 EB |
2722 | pid = m->private; |
2723 | tsk = get_pid_task(pid, PIDTYPE_PID); | |
99f89551 EB |
2724 | if (!tsk) |
2725 | goto out_free; | |
1da177e4 | 2726 | |
27e89ae5 | 2727 | rcu_read_lock(); |
8793d854 PM |
2728 | css = task_subsys_state(tsk, cpuset_subsys_id); |
2729 | retval = cgroup_path(css->cgroup, buf, PAGE_SIZE); | |
27e89ae5 | 2730 | rcu_read_unlock(); |
1da177e4 | 2731 | if (retval < 0) |
27e89ae5 | 2732 | goto out_put_task; |
1da177e4 LT |
2733 | seq_puts(m, buf); |
2734 | seq_putc(m, '\n'); | |
27e89ae5 | 2735 | out_put_task: |
99f89551 EB |
2736 | put_task_struct(tsk); |
2737 | out_free: | |
1da177e4 | 2738 | kfree(buf); |
99f89551 | 2739 | out: |
1da177e4 LT |
2740 | return retval; |
2741 | } | |
8793d854 | 2742 | #endif /* CONFIG_PROC_PID_CPUSET */ |
1da177e4 | 2743 | |
d01d4827 | 2744 | /* Display task mems_allowed in /proc/<pid>/status file. */ |
df5f8314 EB |
2745 | void cpuset_task_status_allowed(struct seq_file *m, struct task_struct *task) |
2746 | { | |
df5f8314 | 2747 | seq_printf(m, "Mems_allowed:\t"); |
30e8e136 | 2748 | seq_nodemask(m, &task->mems_allowed); |
df5f8314 | 2749 | seq_printf(m, "\n"); |
39106dcf | 2750 | seq_printf(m, "Mems_allowed_list:\t"); |
30e8e136 | 2751 | seq_nodemask_list(m, &task->mems_allowed); |
39106dcf | 2752 | seq_printf(m, "\n"); |
1da177e4 | 2753 | } |